In 1994, the military science fiction feature film Stargate was released, directed by Roland Emmerich and co-written by Emmerich and Dean Devlin. The film lays the foundation for all the Stargate productions that come after it, by explaining the notion, function, and history of the Stargate.

The film begins with the unearthing of the Stargate in Giza in 1928. In a present day (1994) military base in Creek Mountain, Colorado, discredited Egyptologist Daniel Jackson (James Spader) enables use of the Stargate when he recognizes that symbols on the cover stones are asterisms in a three dimensional coordinate system. A probe sent through the first Stargate connection revealed survivable conditions on the planet Abydos (which was believed to be billions of light-years away, in the Kaliam Galaxy on the far side of the known universe). A team led by Colonel Jack O'Neil (Kurt Russell) is then ordered to step through the Stargate and identify potential military threats on the other side. Jackson accompanies them to operate the other Stargate with his knowledge of the coordinate system.

The team discovers a slave civilization serving an alien who is posing as the Egyptian god Ra (Jaye Davidson). Ra and his minions have taken human form, dominating the slaves with brute force. With the help of the locals, O'Neil's team is eventually able to instigate a slave rebellion, overwhelming Ra's forces. Ra escapes in his mothership, but O'Neil is able to teleport a nuclear warhead on-board Ra's ship in orbit and detonate it. With Ra dead, the civilization can live in peace; O'Neil and his team return home through the Stargate, but Daniel Jackson stays on the planet with a young local woman named Sha'uri.

In 2011, Stargate Universe, the last Stargate program on television ended its run. Brad Wright announced that there were no more plans to continue the same story in further productions. In 2016, comic publisher American Mythology acquired the rights to publish new Stargate Atlantis stories set within the established franchise canon. This was expanded in 2017 to include new Stargate Universe comics as well, resolving the cliffhanger that ended the show. The predominant story arc thus ran for more than 15 years, including 18 seasons (364 episodes) of programming, and 22 comic book issues as of January 2020. However, a variety of other media either ignore this main continuity or resets it, while maintaining essential elements that define the franchise (mainly, the inclusion of a Stargate device). These include the 2002 animated series Stargate Infinity.

In 2017, the franchise was revived with the announcement of a new prequel web series, Stargate Origins. Episodes premiered on a central "fan hub" for the franchise called Stargate Command, with a season of ten 10-minute episodes.