H. J. Murray wrote a book on the history of this activity and included several Arabic documents pertaining to it called “mikhariq” (“mee-CAR-ihk”). This is the first of three activities that was the subject of a book commissioned by Alfonso X of Castile that includes its “astronomical” variety. (-5[1])A “great” variation of this activity was legendarily developed by Tamerlane. A discovery (15[1])on the Isle of (*) Lewis yielded a hoard of (10[1])items (10[1])used for this activity made mostly from walrus (10[1])ivory. A treatise on this (10[1])activity by the Spanish priest Ruy Lopez (10[1])introduced (10[1])a namesake (10[1])strategy for this activity. This activity evolved from a similar one in India called chaturanga, which also used an eight-by-eight board. For 10 points, name this board game where players seek to win through checkmate. ■END■