Go & Shogi, Made Japanese
The children of chaturanga scattered across the world, but only Japanese shogi has a move found nowhere else: dropping a captured piece back onto the board as your own. Chess doesn't have it. Xiangqi doesn't have it. Among chaturanga-family games, it's said that only honshogi (standard shogi) and kinshogi use captured pieces at all. When this began is disputed — shogi historian Koichi Masukawa, working from what looks like a reference to tsumeshogi (checkmate problems) in the 15th-century Shinsen Yugaku Orai, estimated that the practice of using captured pieces had begun by around that time. What's certain is that the oldest surviving tsumeshogi book (1602) and the oldest surviving recorded game (1607, a match between Sokei Ohashi and Honinbo Sansa) both use captured pieces — by the late 16th century at the latest, shogi had become the game it is today. On the go side, Sansa served Nobunaga, Hideyoshi, and Ieyasu, and the shogunate established stipended houses of professional players — Honinbo, Inoue, Yasui, and Hayashi. That's the moment play became a profession. There's also a widely told story from the postwar years: someone said reusing captured pieces was like abusing prisoners of war, and the professional player Kozo Masuda is said to have shot back that a piece can always serve wherever it's needed — if anything, that's democratic. But accounts differ on who said this to whom and when, so this map places it here as an anecdote, with that caveat attached.