Short answers, pulled from the story.
Koei Tecmo Holdings was formed on the 1st of April 2009 through the merger of Koei, founded in July 1978 by Yoichi and Keiko Erikawa, and Tecmo, founded on the 31st of July 1967 by Yoshihito Kakihara. The combined holding company was initially named Tecmo Koei before being renamed Koei Tecmo in 2014.
Tecmo officially declined Square Enix's proposal on the 4th of September 2008, the same day it announced plans to merge with Koei instead. Koei's president Kenji Matsubara cited a longstanding personal relationship between the two companies' founding families as the key factor that made a deal possible within just two days of opening discussions.
Koei Tecmo is best known for franchises including Dead or Alive, Dynasty Warriors, Ninja Gaiden, Nioh, Nobunaga's Ambition, Fatal Frame, Atelier, Samurai Warriors, Monster Rancher, and Romance of the Three Kingdoms. The company has also contributed to external franchises such as Square Enix's Final Fantasy and Intelligent Systems' Fire Emblem series.
Angelique is the flagship series of Koei Tecmo's Ruby Party division, an otome game visual novel and dating simulation that has been in production since 1994. The first Angelique game holds the distinction of being the first otome game ever made, establishing the template for the genre of visual novel and dating simulations aimed at women.
Yoichi and Keiko Erikawa are the husband-and-wife co-founders of Koei, established in July 1978 in Yokohama. Yoichi, who also uses the pen name Kou Shibusawa, served as company president following Kenji Matsubara's resignation in 2010 and held that position until stepping back to chairman on the 1st of April 2025. Keiko transitioned to director and chairman emeritus at that same transition, also becoming representative director and president of the newly formed Koei Tecmo Corporate Finance.
Tecmo faced two significant legal disputes in 2008. On the 3rd of June 2008, Team Ninja head Tomonobu Itagaki resigned and filed a 145 million yen lawsuit against president Yoshimi Yasuda over unpaid completion bonuses and emotional distress. On the 16th of June 2008, two plaintiffs filed a separate lawsuit on behalf of Tecmo's 300 employees seeking 8.3 million yen in unpaid wages. Earlier, in 1989, Tecmo had been named co-defendant when NFL player Eric Dickerson sued over his likeness in Tecmo Bowl.