http://shmuplations.com/historyofsquare/
This “History of Square” interview with Hironobu Sakaguchi was originally featured in a 1992 bonus edition of Dengeki Super Famicom. Square had only just released Final Fantasy V, so it’s really an account of the first 8 years of the company history, peppered with some humorous anecedotes from their early days. Please note that the italicized text is from the original article; I thought it made sense to leave it in for context and framing this time.
The interview is rounded out by brief commentaries from three of Square’s most famous illustrators: Yoshitaka Amano, Tomomi Kobayashi, and Katsutoshi Fujioka. Finally, Dengeki Super Famicom also issued a questionnaire to Square’s employees, the results of which I’ve appended at the bottom.