London 1851

London 1851 brought leading players from several countries together while the city hosted the Great Exhibition. Howard Staunton conceived and organized the event, which ran from May 26 to July 12. Its international scale and the later publication of a full tournament book helped make it a landmark in organized chess.

Sixteen players competed in a knockout format. They did not all play one another. Instead, they met in short matches, and the loser of each match left the bracket. Draws did not count as wins, so a contest could continue until one player reached the required number of victories. Adolf Anderssen won the tournament, with Marmaduke Wyvill finishing second.

The structure was very different from the round-robin format later used at events such as Nottingham 1936, where every entrant plays every other entrant. London 1851 therefore matters not only for its famous participants but also as an early model of international competitive organization.

The celebrated Immortal Game between Anderssen and Lionel Kieseritzky was also played in London during the event. It was an informal game outside the official bracket, not a tournament round.