Slowest chess move - pre-clock

Until the adoption of the “chess clock” and time controls in the 1860s, chess players could take as long as they wanted to decide on their next move. The slowest confirmed game of chess from this era is the November 1857 final of the First American Chess Congress, played between Paul Morphy (USA) and Louis Paulsen (DEU). In this game, which finished in a draw, the two players took more than 15 hours to play 56 moves (only 53 were officially recorded). Louis Paulsen, who decisively lost the match overall, was responsible for most of the delay, taking as much as 1 hour 15 minutes to decide on his moves.

Before the introduction of time controls, some competitive players were thought to have used slow decision-making as a strategy, taking as much as an hour to decide on each move. Chess tournament organizers feared that this trend might, if taken to extremes, have turned chess games into tests of endurance, rather than mental skill – hence the introduction of the chess clock.