In the early 1970s, the Marriott Corporation, owner of several restaurant chains and Marriott hotels, sought to branch further out into the tourism and vacation industry. The largest of the projects it took on was a chain of state-of-the-art theme parks, each of which would be named "Marriott's Great America" and themed around American history, opening in time for the nation's bicentennial. From the beginning, three parks were planned, as Marriott identified three underserved metropolitan areas that could support a major amusement park: Baltimore–Washington, the San Francisco Bay Area, and Chicago–Milwaukee.

The largest of these, at 850 acres (340 ha), was announced for Laurel, Maryland, in 1972. The proposal was canceled after fierce opposition from local residents convinced officials to deny the park permits, and the plans were moved to Manassas, Virginia, in 1973, where it faced even stronger opposition from local residents and the National Park Service. The planned opening of the flagship park was delayed repeatedly until Marriott abandoned the idea late in the decade.

Meanwhile, the plans for the other two parks proceeded more smoothly. The location in the north of the Chicago metropolitan area was chosen to bring in visitors from Milwaukee and Chicago. Marriott purchased 600 acres (240 ha) of rural land in Gurnee straddling the Tri-State Tollway in August 1972, causing speculation in the Chicago Tribune that an amusement park was planned for the site. The Gurnee park was officially announced on January 29, 1973, along with a hotel and an industrial park. Marriott received approval from local authorities, but the Illinois State Toll Highway Authority would not approve a proposal for an interchange on the tollway leading directly into the parking lot.

Randall Duell was the leader of the design team for the park, who created two nearly identical plans for the Gurnee park and the sister park in Santa Clara, California. Duell was a veteran theme park designer and for the Great America parks. With an overarching Americana theme in mind, Marriott's designers traveled across the country, observing styles and collecting artifacts to help inform an authentic atmosphere.

Instead of utilizing a spoke-hub design found at other theme parks, the park was designed on Duell's theme park layout design named the "Duell loop," where guests visit each themed area while employees worked in the middle of the park. The original themed areas of the park are:

The groundbreaking ceremony was held on Flag Day, June 14, 1974. During the construction of the park, 12 houses and the street where they were located on were demolished to make way for the park's 6-lane toll road, which would serve as the park's main entrance and exit. It cost $72,750,000 in total to construct both of the Great America parks.

The park officially opened on May 29, 1976, two months after the Marriott's Great America in California. The park was an immediate success due in part to coinciding with the bicentennial. At its opening in 1976, Marriott's Great America featured three roller coasters, Willard's Whizzer, Turn of the Century, and The Gulf Coaster. The park had also included other flat rides throughout the park. These attractions included the double-decker Columbia Carousel which is the second-tallest carousel in the world, and the Sky Whirl, a unique, 110-foot-tall (34 m) "triple ferris wheel" custom-designed for Marriott. Transportation rides included Delta Flyer and Eagle's Flight, two one-way gondola sky car rides.

From the beginning, the park made use of the Looney Tunes characters as costumed figures to interact with the park attendees. Each themed area had its own set of costumes for park employees, and the design of buildings, shops and restaurants were all unique to each theme. A seventh area, The Great Southwest, was planned from the beginning as a potential expansion but was never constructed.

The park's second season in 1977 saw the installation of several new rides. The 285-foot-tall (87 m) Sky Trek Tower opened in Carousel Plaza as the tallest freestanding structure in Lake County, Illinois. Sky Trek Tower was built as and still remains, the tallest freestanding structure in Lake County, Illinois. Also added was Southern Cross, a third gondola sky car ride which offered a round trip and a much higher view than the other two, whose station replaced the removed Gulf Coaster. A few new spinning rides were added, such as Big Top, Davy Jones' Dinghies and Hay Baler.

Two new attractions were added in 1978. The park's first children's section, named Fort Fun, opened in the section designated the Yukon Territory, which relocated the Saskatchewan Scrambler to Hometown Square where it was renamed to Hometown Fun Machine. Additionally, Great America's fourth roller coaster, Tidal Wave, a Schwarzkopf Shuttle Loop, opened in Yankee Harbor. The Pictorium, an IMAX theatre, opened in 1979, and claimed to have the world's largest screen, at 64.5 by 88.25 feet (19.6 × 26.9 meters).

The Turn of the Century roller coaster closed and was rethemed in 1980. Two vertical loops were added, along with two tunnels and the "new" ride was re-themed and renamed Demon. The ride featured an original theme song and new demon-themed elements. American Eagle, a racing wooden roller coaster, opened in 1981. The tracks share a drop of 147 feet (45 m) and they reach speeds of 66 mph (106 km/h). It opened as the tallest, fastest and longest twin racing wooden coaster.

The Picnic Grove was added in 1982, allowing for more company outings and corporate events to take place at the growing theme park. No new rides were added that year, and several small rides were removed in the last years of Marriott ownership. Southern Cross was removed in 1983. That same year, The Edge, an Intamin first-generation freefall ride, was added to much fanfare. Bottoms Up, a Chance Trabant ride and Traffique Jam were removed at the end of the 1983 season.

The last ride Marriott added to the park was White Water Rampage in 1983, an Intamin water rapids ride. The ride was added to Orleans Place, which required the removal of small rides such as Traffique Jam. The Orleans Orbit was moved from its original Orleans Place location to Hometown Square, and became simply The Orbit.

By the mid-1980s, the Marriott Corporation was disappointed with the financial performance of its theme park division, with lower profits than the company expected, in part because the third and largest of its Great America parks was never realized. As a result, Marriott decided to focus on its core businesses and began searching for buyers for its two amusement parks. While the Great America park in Santa Clara, California, was sold to the city of Santa Clara, Bally Manufacturing, the then-parent company of the Six Flags Corporation, offered to purchase the Gurnee park for $114.5 million. The deal was finalized on April 26, 1984, and as a result Six Flags also acquired the right to use the Looney Tunes characters at all of its other parks.

After the sale of the park to Bally Manufacturing in 1983, the park was re-branded as Six Flags Great America starting in 1984. Regarding the acquisition of the park, Bally CEO Robert Mullane stated that it would be "foolish to change anything major" at the park.

Less than a month after the purchase, a software failure caused a car on The Edge, a freefall ride, to be stalled at the top of the lift shaft before moving forward into its drop position. The car was stuck in this position for a short period of time before it dropped in the lift shaft, causing injuries to all three occupants. Despite many attempts to reopen The Edge with installation of anti-rollback devices by Intamin, the ride was never able to escape the stigma of its 1984 accident. The ride was removed in 1986.

In 1985, Six Flags added Z-Force to the County Fair area, a one-of-a-kind Intamin space diver roller coaster that closed in 1987 and was the only one ever manufactured. The site was later used for Iron Wolf, which opened in 1990. Z-Force was relocated to Six Flags Over Georgia as part of Six Flags' (now discontinued) Ride Rotation Program. At the end of 1991, the ride went to Six Flags Magic Mountain, where it operated as Flashback before closing in 2003, and being demolished in 2007. Power Dive was added in 1987 to take over the spot where The Edge had stood. Power Dive was an Intamin Looping Starship ride; it swung back and forth before eventually rotating a complete 360 degrees a few times.

While operating the Six Flags chain, Bally found that the excess resources demanded and high seasonal fluctuations of the theme park business made it an unnecessary burden on its core interests. In 1987, Bally sold Six Flags to Wesray Capital Corporation and a group of Six Flags managers. Several acquisitions were re-sold or closed, while Wesray moved the company's focus from theming to major attractions. This ushered in an era of major new rides and roller coasters at Six Flags parks like Great America.

1988 saw the first of the new coasters, with the addition of the massive roller coaster Shockwave, an Arrow Dynamics mega-looper, opening in Orleans Place section of the park on June 3, 1998. Shockwave was the world's tallest roller coaster at the time it opened and was surpassed the following year by Cedar Point's Magnum XL-200. It also featured a record seven inversions, which was surpassed in 1995 by PortAventura Park's Dragon Khan. When Six Flags Great Adventure's Sarajevo Bobsled, an Intamin Bobsled roller coaster, closed in 1988, it was moved to Great America and became Rolling Thunder in 1989. It was added between Demon and Whizzer.

For 1990, Bolliger & Mabillard constructed their first ever roller coaster with Iron Wolf, a compact steel stand-up coaster. It opened on Z-Force's former spot in County Fair. In the following year, Condor was added to Orleans Place in 1991, next to Shockwave. Tidal Wave was closed at the end of the 1991 season. It was relocated to Six Flags Over Georgia where it operated as Viper from 1995 to 2001, then to Kentucky Kingdom as Greezed Lightnin' from 2003 to 2009.

The first collaborations between Six Flags and Time Warner, the majority owner of Six Flags, came in 1992, as Bolliger & Mabillard constructed their first inverted roller coaster, Batman: The Ride, to replace Tidal Wave. Batman was unlike any other roller coaster at the time, as it opened as one of the first inverted roller coasters and featured five inversions. The ride was met with positive reception that lines stretched out of the ride area and across large parts of the park. The surrounding area of Yankee Harbor was re-themed after the Batman films, with The Lobster being renamed the East River Crawler, a name which it retained until it was moved to Hometown Square under its original name in 2016. Batman: The Ride was awarded landmark status by the American Coaster Enthusiasts (ACE) at their annual convention in 2005.

To add to the hype around Batman from the opening of Batman: The Ride and the mega-hit film Batman Returns, the Batman Stunt Show opened in 1993 in a brand-new amphitheater located past Demon; which would later come to be known as the Southwest Territory Amphitheater. Six Flags and Time Warner had debuted The Batman Stunt Show at Six Flags Great Adventure the year prior, with great success. The theater would be a popular venue with several stunt shows for years to come, before being torn down for the 2016 addition of the Justice League: Battle for Metropolis dark ride.

Space Shuttle America, a motion simulator ride, was built in 1994 near Sky Trek Tower. In addition to its purpose-made titular film, Space Shuttle America was home to three other shows during its lifetime: Escape from Dino Island 2 – 3:D, Stargate – SG:3000, and Superstition during the yearly Fright Fest Event.

In 1995, construction began on a new themed area for the park. The area, called Southwest Territory, was originally intended to be added to the park in 1979, with the Southern Cross ride intended to bring guests to it, but was never constructed. The first ride built for the new area was Viper, a wooden roller coaster based on the Coney Island Cyclone and themed after a snake oil salesman. Although smaller in stature than American Eagle, this twister-style coaster features many more instances of airtime during the ride. It was built next to Rolling Thunder, which was removed later the same year to make room for the new area. The ride was relocated to The Great Escape in New York, where it operated as Alpine Bobsled until 2023.

Southwest Territory opened in 1996, with a desert theme based on the Old West. Three new rides were added: River Rocker, a pirate ship ride; Chubasco, a teacup ride; and Trail Blazer, a Zamperla Joker. The Big Top was moved in from County Fair and renamed Ricochet. Viper's entrance, which had previously been located in Hometown Square, was moved to Southwest Territory entrance. The amphitheater that has previously been home to the Batman Stunt Show was renamed the Southwest Territory Amphitheater, debuting the Warner Bros. Western Stunt Show. This show followed the misadventures of three outlaws as they tangled with characters from Western films such as Maverick, Blazing Saddles and F Troop. The Western Stunt Show ran for three seasons and was replaced in 1999 by the Butch Cassidy and the Sundance Kid Stunt Show.

Giant Drop, an Intamin second-generation drop tower and Dare Devil Dive, a skycoaster, were added in 1997. Giant Drop was placed on the southwest side of Southwest Territory across from the mission, and was themed to be an ore excavator in the fictional Loco Diablo Mine. Dare Devil Dive opened in County Fair.

Plans for expansion outside the amusement park started in the fall of 1997 with the planning of Six Flags Entertainment Village, an entertainment complex that would be located across Interstate 94. Opposition for Six Flags Entertainment Village arose in November 1998 with the citizens group Citizens United for a Residential Village of Gurnee (CURV) forming, with the concern of road congestion and rising tax prices.

In 1998, Camp Cartoon Network opened as a sub-section of Yukon Territory with five new rides, including Spacely's Sprocket Rockets (a Vekoma junior roller coaster), Scooby-Doo's Mystery Machine, Yogi's Yahoo River, Rocky Road's Rescue Service and Bedrock Boulder Roller. Additionally, Bugs Bunny Land was renamed Looney Tunes National Park and included the Looney Tooter Choo Choo Train, the Waddaview Charter, Porky's Buzzy Beez, Petunia's Lady Bugz, Looney Tunes Lodge Foam Ball Factory, Pepe Le Pew's Peak and the Nature Trail.

Bolliger & Mabillard constructed Raging Bull in 1999, a hyper-twister coaster that was added to Southwest Territory. This 202-foot-high (62 m), 73 mph (117 km/h), and 5,057-foot-long (1,541 m) ride was built on the former lot used by Rolling Thunder. In late October, the park had officially cancelled their Entertainment Village project.

The park celebrated its silver (25th) season in 2000. This was the last year for the Sky Whirl and the Hay Baler ride. That same year, an accident involving a guest occurred on the Cajun Cliffhanger ride, which led to its removal.

In 2001, two inverted shuttle coasters were added: an Intamin impulse coaster named Vertical Velocity (stylized as V2); and Déjà Vu, a Vekoma Giant Inverted Boomerang ride to replace Sky Whirl and Hay Baler. Vertical Velocity was added to Yankee Harbor, with the swing ride Whirligig moving closer to the lift hill of Batman: The Ride to make room for Vertical Velocity.

In the summer of 2002, plans were announced to remove Whizzer, closing on August 11 of that year. The plan to remove the coaster, which is one of two Speedracer models left in the world, was met with outrage from the public, particularly because the intended replacement was a major thrill ride. The backlash led to Six Flags deciding on August 3 to cancel their plans to replace Whizzer, and instead elected to replace Shockwave. Power Dive was also removed, due to maintenance problems.

In 2003, Bolliger & Mabillard constructed Superman: Ultimate Flight in Orleans Place, on the plot of land where Shockwave stood. It was the Midwest's second flying roller coaster, the first being X-Flight at Geauga Lake. The layout of the ride is identical to versions of the ride at Six Flags Great Adventure and Six Flags Over Georgia. Shockwave had partially stood in the parking lot, and for Superman, the entire landscaping of the ride area was redone. Additionally, the Ameri-Go-Round carousel in County Fair was removed at the end of the 2003 season.

Mardi Gras, a new themed area, which annexed a portion of Orleans Place, was added in 2004. It was built in the area where Power Dive and Cajun Cliffhanger had stood. A spinning wild mouse coaster named Ragin' Cajun was added, along with a HUSS Top-Spin model named King Chaos, a Zamperla Rockin' Tug model named Jester's Wild Ride and a Zamperla Balloon Race model named Big Easy Balloons. The same year, the removed Ameri-Go-Round from County Fair was replaced by Revolution, a HUSS Frisbee ride from Six Flags Great Adventure. On September 17, 2004, the Six Flags Hurricane Harbor water park was officially announced. It would become the seventh Hurricane Harbor water park to open, and would be built on a parking lot behind Raging Bull and Viper. Groundbreaking began in November 2004, with grand opening on May 28, 2005.

In December 2005, stockholders approved a plan offered by Daniel Snyder of Red Zone, LLC to take over management of Six Flags, Inc., following a fierce stockholder revolt due to rising financial concerns. Snyder appointed former ESPN executive Mark Shapiro as the new CEO of Six Flags, after Kieran Burke was ousted from the company. Snyder and Shapiro's plan of action was to move Six Flags away from Premier Parks' thrill-heavy focus and move more toward a family-friendly environment.

In 2006, Six Flags announced it would replace its sign that sits along Interstate 94 during the off season. The sign, which had been standing since the park opened in 1976, was replaced with a smaller one featuring an LED screen. The new sign went up within a week after the old one was taken down in December 2006, and uses the old sign's post.

2007 marked the introduction of the electronic Flash Pass virtual queue system to Six Flags parks, including Great America. For an additional fee, guests can purchase a Flash Pass and wait in line for a ride without actually standing in line. The system, themed after the DC Comics character, replaced an existing punch card system that was used at the park.

As part of the new focus on entertainment, Six Flags introduced a new stunt show, Operation SpyGirl, in the Southwest Territory Amphitheater for the 2007 season. Operation SpyGirl was an original live-action production created by Joel Surnow, co-creator of the Fox television series 24. Operation SpyGirl debuted in May, and closed for the season in August. The show marked several new ventures for Six Flags, including pre-show entertainment in the waiting area, which set up the storyline that the evil archvillain Max Condor had stolen the "Super Viper Rocket" from the agency for which SpyGirl works – as well as a merchandise cart outside selling "SpyGirl" themed merchandise. Operation SpyGirl did not return in 2008. Other new shows introduced for the 2007 season were "Spirit of America" at the reflection pond in front of the Columbia Carousel, and "Show Stoppin'" in the Grand Music Hall.

The tented area in front of the American Eagle was converted into Wiggles World in 2007, a third children's area themed after the Wiggles, featuring five new rides. American Eagle's entrance was relocated to the right of the tent, utilizing part of the entrance building for the adjacent Dare Devil Dive skycoaster to accommodate the Wiggles area.

Great America added The Dark Knight Coaster in 2008, an indoor Mack wild mouse roller coaster themed after the film and located in Orleans Place. The ride is located indoors, mostly in the dark, and has a storyline based around Batman and The Joker. The Theater Royale was converted into a queue building for the ride, which features a preshow starring Aaron Eckhart, reprising his role as Harvey Dent from the film. Additionally, Splashwater Falls closed for the 2007 season early on, and was removed in March 2008.

For 2009, Six Flags replaced Déjà Vu with Buccaneer Battle, a pirate-themed boat ride in County Fair designed by Mack Rides. The ride consists of 14 eight-passenger boats navigating a channel 450 feet (140 m) long. During the ride, there are numerous interactive water elements that can be controlled by passersby.

In 2010, Great America acquired the Little Dipper, a "kiddie" wooden roller coaster that had previously operated at Kiddieland Amusement Park in Melrose Park, a western suburb of Chicago, from 1950 until 2009. It was placed outside Bugs Bunny National Park and opened to the public on May 27, 2010. The park also introduced the Glow in the Park Parade, which was already featured at other Six Flags parks, and MagiQuest was added to the County Fair Games Gallery in place of the Wii Experience.

Space Shuttle America, the park's motion simulator ride that had been closed for two years, was removed during the 2010 season. On May 26, 2010, Great America filed a petition with the Village of Gurnee seeking to exceed the village's 125 feet (38.10 m) height limit. Six Flags was considering installing Chang, a roller coaster moved after the closure of Kentucky Kingdom, in place of the shuttle. However, the park confirmed it was abandoning those plans in July 2010 and that the space would instead be used for Riptide Bay, a 3-acre (12,140.57 m2; 130,680.00 sq ft) addition to the Hurricane Harbor water park.

In late 2010, Six Flags began removing some licensed properties from concessions and attractions, with Wiggles World being renamed Kidzopolis and having Wiggles branding and theming removed for 2011. MagiQuest closed due to a lack of popularity and Great America Raceway, an original ride from 1976, was closed and removed. At the end of the 2011 season, Iron Wolf was closed and removed. It was relocated to Six Flags America, rebranded as Apocalypse, before it was converted into a floorless roller coaster and renamed Firebird in the 2019 season. For 2012, the former sites of Splashwater Falls and the Great America Raceway in County Fair were taken over by a new wing coaster from Bolliger & Mabillard with 5 inversions, a 12-story drop and speeds of up to 55 mph. X-Flight was the second roller coaster of its type in North America and the fourth in the world.

The Glow in the Park parade was replaced in 2013 with IgNight – Grand Finale to the park. IgNight was held in Hometown Square, in front Hometown Square's Scenic Railway Train Station. Six Flags announced that 2013 would be the "Season of Backwards" at Great America, with Batman: The Ride, Viper and the Blue Train on American Eagle all running backwards for some part of the season. At the end of the season, Ragin' Cajun closed and was relocated to Six Flags America in 2014. For 2014, the park received Goliath, a 165-foot-tall (50 m) wooden roller coaster built by Rocky Mountain Construction. The ride broke world records for the steepest drop, fastest speed and longest drop on a wooden coaster, and was built on the plot of land where Iron Wolf formerly stood. Three former kiddie rides were reinstalled in the all-new Hometown Park children's area in 2015, located in Hometown Square. That year, the park held the "40 Seasons of Thrills" celebration, a festival which celebrated the park's history.

In 2016, Great America introduced Justice League: Battle for Metropolis, a 4D interactive dark ride, alongside a new themed area: Metropolis Plaza. The area is themed after the city of Metropolis from DC Comics, and is located between Southwest Territory and County Fair. Six Flags also announced plans to add virtual reality headsets to Raging Bull by the end of that season, but Demon received the VR headsets instead, creating a new 'Rage of the Gargoyles' ride experience. The Orbit, an original 1976 attraction, closed on August 6, 2016. At the end of the season, The Jester's Wild Ride was also removed.

The Joker, an S&S 4D Free Spin roller coaster, was added to Yankee Harbor for the 2017 season. The park also announced that The Orbit would not return, and East River Crawler was relocated to the former site of The Orbit and its name returned to The Lobster, the original name for the ride. For the first month of the season, VR headsets were added to Giant Drop, which became the "Drop of Doom".

Mardi Gras Hangover, a fire ball attraction, was added in 2018. The ride would be a 100-foot-tall (30 m) looping flat ride which at the time was the largest of its kind in the world. King Chaos closed on August 26, 2017, to make way for the new ride. On April 11, Six Flags Great America announced that Holiday in the Park would also debut at the park November 23, 2018.

On April 27, 2019, the park confirmed via their official Twitter account that Pictorium would be demolished to make way for new thrills. On August 30, 2018, the park announced that Maxx Force would open in 2019 replacing the Pictorium. Manufactured by S&S Worldwide, it is an air launch roller coaster that breaks three world records and features the fastest acceleration in North America. On October 9, 2018, the Rockford Park District announced a potential lease agreement with Six Flags Great America for the park to operate Magic Waters (now Six Flags Hurricane Harbor Rockford). On December 11, 2018, the lease deal was made official and Six Flags took control of the water park on April 1, 2019.

In March 2020, the park announced the delay of the opening for the 2020 season due to the COVID-19 pandemic, and was ordered to stay closed until the "Phase 5" of Illinois' phased re-opening plan. Hurricane Harbor re-opened to the public on July 20, 2020, with safety protocols in place using the name Hurricane Harbor Chicago. Although the full re-opening of the park was deemed "unlikely" by the Lake County Health Department, the park opened with Holiday in the Park Lights, a holiday lights event and Holiday in the Park Lights Drive-Thru, a drive-through holiday event.

On March 22, 2021, the connected Hurricane Harbor park became separately gated from the theme park and would be renamed as Hurricane Harbor Chicago as the chains 27th theme park. In the following month on April 24, 2021, the park reopened at 25% capacity under Illinois order due to the pandemic with safety protocols in place. The park opened at full capacity on June 11, 2021, and all mask mandates were dropped.

On March 24, 2022, the park announced DC Universe, a DC Comics themed area. The area is a re-theme of Yankee Harbor. It would feature 3 "re-imagined" rides, The Flash: Vertical Velocity, a re-theme of Vertical Velocity, DC Super-Villains Swing, a re-theme of Whirligig and Aquaman Splashdown, a re-theme of Yankee Clipper. Opening day of DC Universe was slated for April 15, 2022, when the park opened, but due to "excessive rain and supply chain issues," the area would open later in spring. DC Universe opened on April 23, 2022.

In 2023, the park confirmed that Dare Devil Dive and Buccaneer Battle would be permanently closed, following removal from the park map. On August 30, 2023, the park announced that Sky Striker, a large pendulum ride, would open in 2024. At the end of the 2023 season, the park announced that Revolution and Mardi Gras Hangover would be closed permanently. Both rides were subsequently bought and relocated to Niagara Amusement Park & Splash World, where they remain in storage.

On August 15, 2024, the park announced the construction of a B&M Dive Coaster on the former site of Buccaneer Battle for the 2025 season called Wrath of Rakshasa. It holds records for steepest drop at 96 degrees and most inversions on a dive coaster with five inversions. It opened on May 31, 2025.

In early November 2024, it was announced in a press release, following the merger between Six Flags and Cedar Fair, that Six Flags Great America would receive a new kids area, alongside 50th anniversary celebrations, and park enhancements, as part of Six Flags' $525 million investments for the 2026 season. No specific details relating to the kids area were elaborated.