Kingdom Come: Deliverance - One Million Copies Sold

According to this Czech interview with Martin Frývaldský, CEO of Warhorse Studios, as well as this tweet from Daniel Vávra, the game's creative director, Kingdom Come: Deliverance has managed to sell a million copies across all platforms within a week of release. I guess this means that there definitely are plenty of people who want realistic historical RPGs, and that it is indeed possible to crowdfund a successful open world game.