Helpmate

A helpmate is a type of chess problem in which both sides cooperate so that Black ends up checkmated. In a helpmate in n moves, written h#n, Black moves first and White second, each side making n moves, and White's nth move delivers the checkmate; every move must still be legal under the rules of chess. A helpmate in two, for instance, runs Black move, White move, Black move, White checkmate. Composers present a problem as having one solution unless they say otherwise, and variety comes from several complementary solutions, from twinning, where small changes to one diagram yield a set of related problems, and from the duplex form, which is also solved with White moving first. The genre begins with a problem by the German master Max Lange, published in Deutsche Schachzeitung in December 1854. Sam Loyd published the first helpmate with Black to move in The Chess Monthly in 1860, and the first completely sound example was by A. Barbe of Leipzig in 1861. The term help-mate comes from T. B. and F. F. Rowland's The Problem Art of 1897, and helpmates are now second in popularity only to the directmate and no longer counted as fairy chess.