It was founded in 2003 by Joe Bostic, Michael Legg and Steve Tall, programmers formerly of Westwood Studios, after that company was closed down earlier that year.

[needs update] On April 27, 2009, it was announced that Petroglyph would be working on a massively multiplayer online real-time strategy game (MMORTS).

[4][5] On June 17, 2010, Trion/Petroglyph for their End of Nations MMORTS won multiple E3 2010 Awards for Best Booth, Best MMO, Best RTS, and others.

On February 22, 2011, Petroglyph announced their free-to-play multiplayer online battle arena game title, Rise of Immortals.

On January 18, 2013 Petroglyph launched social guessing game Coin a Phrase on Apple's App Store.