In a recent interview with Denfaminicogamer, founder of Koei (now Koei Tecmo) Yoichi Erikawa, also known as Kou Shibusawa, talked about his early days as a game designer and what it was like to make games in the early 1980s, when Japan’s gaming landscape was still taking shape. Despite there being virtually no established game industry nor supply chains for PC games, Erikawa’s first game, Kawanakajima no Kassen, sold 10,000 copies.
Kawanakajima no Kassen is a war simulator PC game created by Erikawa in 1981. Drawing on real-life historical events, the game put players in the Sengoku Period, in the midst of the clash between the Takeda and Uesugi clans. The game incorporates not only battle, but realistic elements of being a feudal lord in Japan, like managing recruits, finances and flood control.

Erikawa comments that he never intended to create a commercial product with Kawanakajima no Kassen. It was a personal project, developed out of his passion for history and newfound fascination with programming. Erikawa would work on it a night, after finishing his day job. “I was making the game while learning about the PC that my wife (Keiko Erikawa) bought for me, and it gradually became more entertaining. Before I knew it, my game grew increasingly polished, and I played it every day.”
Then, at his wife’s suggestion, Erikawa decided to try and see if other people would be interested in his game. They placed an advertisement in a computer magazine, hoping to sell around 10 copies. “At most, I thought we’d sell 20,” Erikawa admits.

But once the orders started coming in, Erikawa and his wife were overwhelmed. With no distribution channel, they had to produce and ship the game themselves. “It was all done by hand. We had no employees, so we asked our neighbors, including police officers’ wives from the nearby housing complex, to help copy the cassette tapes, label them, and package them.” But despite the humble start, Kawanakajima no Kassen sold approximately 10,000 copies, which is a staggering number for the time.
The unexpected success of his first game led Erikawa to consider developing more games. “Users started calling, asking for more,” he recalls. “People wanted games about Nobunaga, Ieyasu, and Hideyoshi (other Sengoku period warlords). Others asked for World War II TRPGs. That’s when I realized there was a real demand.”

This demand led to the development of Nobunaga’s Ambition in 1983, a game that’s considered to be one of the first historical simulators and has since grown into a franchise with over 40 games. Erikawa designed the game, while the programming was done by talented college students Koei hired as part-timers.

Recounting how Koei officially become a software company, Erikawa comments, “I hadn’t even thought of the phrase ‘entering the game business.’ Or rather, there was no such thing as a game industry or gaming business back then. At the time, the PC world was driven by four magazines known as the “big four”: ASCII, RAM, I/O, and Microcomputer. Amateur PC users were influenced these magazines, and gradually became more and more absorbed in PCs, turning into geeks. And one by one, business owners emerged from this userbase. I think I was one of them.”
Kawanakajima no Kassen is available on PC (Steam), although at the time of writing, it is only playable in Japanese.
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