Short answers, pulled from the story.
Eidos Interactive traces its origins to Domark, founded in 1984 by Mark Strachan and Dominic Wheatley, two advertising account executives in London. In 1995, Domark was acquired by a video compression software company called Eidos, and the merged publishing operation became Eidos Interactive in 1996.
Eidos Interactive's flagship franchises included Tomb Raider, developed by Core Design and first released in October 1996; Championship Manager, first released in September 1992; Deus Ex, developed by Ion Storm; Hitman, developed by IO Interactive; Thief; and Legacy of Kain.
Square Enix completed its takeover of Eidos on the 22nd of April 2009 and fully merged the company into Square Enix Limited by the 10th of November 2009. The acquisition was backed by Warner Bros., which was the majority stakeholder in Eidos at the time.
Games publisher SCi made a takeover bid for Eidos on the 22nd of March 2005, one day after a competing offer from private equity firm Elevation Partners. Elevation Partners, led by former Electronic Arts president John Riccitiello, had proposed an injection of funds to keep Eidos solvent; SCi's offer prevailed after Elevation withdrew in late April, with the deal finalised on the 16th of May 2005.
After Square Enix absorbed Eidos, the Tomb Raider franchise remained with Square Enix. In August 2022, Embracer Group completed the purchase of Crystal Dynamics, Eidos-Montreal, and the Tomb Raider intellectual property as part of a larger deal that also included Deus Ex, Thief, and Legacy of Kain.
Ian Livingstone was recruited as the writer of Domark's first game, Eureka!, in 1984 and subsequently invested in the company. He joined Domark's board in 1992, became executive chairman when Eidos floated on the London Stock Exchange in 1995, stepped down to creative director in September 2002, became product acquisition director under SCi in 2005, and was named Life President of Eidos when Square Enix completed its takeover in April 2009.