Akiba Kiwelowicz Rubinstein (1 December 1880 – 15 March 1961) was a Polish chess Grandmaster at the beginning of the 20th century. He was scheduled to play a match with Emanuel Lasker for the World Chess Championship in 1914, but it was cancelled because of the outbreak of World War I. In his youth, he defeated players including José Capablanca and Carl Schlechter. His later life, however, was plagued by mental illness.