From Japanese Wikipedia http://ja.wikipedia.org/wiki/スクウェア_(ゲーム会社):
Square Co Ltd was a Japanese video game company. The 1 of April 2003 Square was merged with Enix to form the company Square-Enix.
The company started by Masashi Miyamoto in october 1983, as a software developing section for Miyamoto's father's electronics company Denyusha in Tokushima, but became independent in september 1986. When started, the company was worth 10 million yen. The 31st of March 2002 the company was worth 12 billion yen. It also has deep connections with Shikoku Ginko (Shikoku Bank), which the current director Tomoyuki Takeichi originally came from.
In 1984, about half a year after its forming, the company started to develop games, with a staff of 10 persons. The first games wer adventure games and role playing games for the NEC PC 88. They scenarios themselves got good reviews, but at this time they already focused on the visuals. Games like "Will Death Trap II", that contained some animation, "Alpha", which usd a lot of anime style visuals, and Mutsumi Inomata illustrations for the front cover, and "Cruise Chaser Blassty" (togheter with Nippon Sunrise), a game with strong influences from the robot animes, got good reviews in the magazines. They also performed ports for other companies.
In 1985 they licensed with Nintendo to produce games for the Famicon. They showed interest in the Famicon Disk System, and formed together with PC makers the group DOG (Disk Original Group), but failed to produce hit games and considered to leave the market. It was the game Final Fantasy, developed by Hironobu Sakaguchi (later vice director) in 1997 that saved Square. With the hit of Final Fantasy, they got a foothold and released the Saga series, the Seiken Densetsu series and many other role playing games and quickly became one of the biggest game makers.
Final Fantasy was a big cash cow for the company. At the time of the release of Final Fantasy II, they opened a shop for Final Fantasy goods in Yoyogi, something that was the on the tounge of all game fans. This shop sold goods from several companies, all licensed by Square, like books, illustrations, coffee mugs and other things.
In 1996, when they first contributed to Sony's Playstation with Tobal no.1 and the introduction of the game distributor DigiCube, they cut the ties with Nintendo, and were on such bad terms that the current director Yamauchi, regarding the release of games for hand-held platforms, told them "I would rather die than let them." In the midst of this, in 1999, Square entered the scene of Nintendo's Game Boy's rival machine, Bandai's Wonder Swan, releasing several games for the console and contributed largely to its sales.
In 2002, they repaired their connections with Nintendo and again released games for their consoles.
In May 2000, Nao Suzuki took over Tomoyuki Takeichi as director. Also, when the company announced in 2000 that they were to concentrate only on Final Fantasy products, a lot of the staff quit and formed their own developing companies, such as Monolith, Brownie Brown, Sacnoth Alphadream corporation and others.
To market Electronic Arts' games in Japan, they formed the company "Electronic Arts Square". And similarly, in America, the company "Square Electronic Arts LLC" was formed.
In 2001, they faced a huge economic loss with the movie Final Fantasy. Nao Suzuki took the reponsibility and quit the company and was replaced by Yoichi Wada. They recieved financial aid from Sony Computer Entertainment to improve the situation. It is said that they prior to this also requested aid from Nintendo, but that they could not agree on a deal; mainly because that Nintendo, who at the time were still suspicious towards the concept of online gaming, requested that Square shut down the "PlayOnline" section. This is, however, just an unconfirmed rumour.
The 26th November 2002, Square announced that they were merging with Enix and became Square-Enix. It is said that this was Enix' way of saving Square, but in fact, Square's economy was already on the rise at this point