Boden's Mate is a checkmating pattern in chess characterized by bishops on two criss-crossing diagonals (for example, bishops on a6 and f4 delivering mate to a king on c8), with possible flight squares for the king being occupied by friendly pieces or under attack by enemy pieces. Most often the checkmated king has castled queenside, and is mated on c8 or c1. Many variants on the mate are seen, for example a king on e8 checkmated by bishops on g6 and a3, and a king on f1 checkmated by bishops on h3 and b6. Often the mate is immediately preceded by a sacrifice that opens up the diagonal on which the bishop delivers checkmate, and the mate is often a pure mate (as is the case for all but one of the examples given here). The mate is named for Samuel Boden, who played a famous early example of it in Schulder–Boden, London 1853. However, it had been known previously from the game Horwitz–Popert, Hamburg 1844. History Boden's Mate is characterized by a king being mated by two bishops on criss-crossing diagonals, with possible flight squares blocked by friendly pieces. Samuel Boden, for whom the mate is named, administered an early example of it in the friendly game Schulder–Boden, London 1853. That game went 1.e4 e5 2.Nf3 d6 3.c3 f5 4.Bc4 Nf6 5.d4 fxe4 6.dxe5 exf3 7.exf6 Qxf6 8.gxf3 Nc6 9.f4 Bd7 10.Be3 0-0-0 11.Nd2 Re8 12.Qf3 Bf5 13.0-0-0? (13.Bd5 is better) 13...d5! 14.Bxd5? (allowing a forced mate; better is 14.Rde1, losing a piece) 14...Qxc3+ 15.bxc3 Ba3#, giving the final checkmate position shown in the diagram. However, the mate had been known before that from the game Horwitz–Popert, Hamburg 1844 (see diagram). There, Black set a trap with 1...Bb8, which White fell into with 2.Rxd5?. Instead of playing the winning 2...Qxh2+ 3.Qxh2 Rxh2+ 4.Kxh2 c6+ (5.Re5 Nxe5 6.dxe5?? Rxd1) Black blundered with 2...c6??. After that White could not save his rook because of the threatened mate in two. Instead, he surprised Black with 3.Rh5! Qxh5 4.Qxc6+! bxc6 5.Bxa6#. Typical pattern Boden's Mate has occurred in many later games, usually, as in the Boden and Horwitz games, after the losing king has castled on the queenside, and the winner sets up the mate by a queen sacrifice on c3 or c6. Perhaps the most famous example of Boden's Mate is the so-called Peruvian Immortal game, Canal–NN, simultaneous exhibition, Budapest 1934: 1.e4