During World War I World War I began in midsummer 1914, bringing international chess to a virtual halt for more than four years. Capablanca won tournaments in New York in 1914, 1915, 1916 (with preliminary and final round-robin stages) and 1918, losing only one game in this sequence. In the 1918 event, Marshall, playing Black against Capablanca, unleashed a complicated counterattack, later known as the Marshall Attack, against the Ruy Lopez opening. It is often said that Marshall had kept this secret for use against Capablanca since his defeat in their 1909 match; however, Edward Winter discovered several games between 1910 and 1918 where Marshall passed up opportunities to use the Marshall Attack against Capablanca; and an 1893 game that used a similar line. This gambit is so complex that Garry Kasparov used to avoid it, and Marshall had the advantage of using a . Nevertheless, Capablanca found a way through the complications and won. Capablanca was challenged to a match in 1919 by Borislav Kostić, who had come through the 1918 tournament undefeated to take second place. The match was to go to the first player to win eight games, but Kostić resigned the match after losing the first five. Capablanca considered that he was at his strongest around this time.
During World War I World War I began in midsummer 1914, bringing international chess to a virtual halt for more than four years. Capablanca won tournaments in New York in 1914, 1915, 1916 (with preliminary and final round-robin stages) and 1918, losing only one game in this sequence. In the 1918 event, Marshall, playing Black against Capablanca unleashed a complicated counterattack, later known as the Marshall Attack, against the Ruy Lopez opening. It is often said that Marshall had kept this secret for use against Capablanca since his defeat in their 1909 match; however, Edward Winter discovered several, games between 1910 and 1918 where Marshall passed up opportunities to use the Marshall Attack against Capablanca; and an 1893 game that used a similar line. This gambit is so complex that Garry Kasparov used to avoid it, and Marshall had the advantage of using a . Nevertheless, Capablanca found a way through the complications and won. Capablanca was challenged to a match in 1919 by Borislav Kostić, who had come through the 1918 tournament undefeated to take second place. The match was to go to the first player to win eight games, but Kostić resigned the match after losing the first five. Capablanca considered that he was at his strongest around this time.