Reminiscent of Dorando Pietri's final-lap ordeal when the Olympics were held in the same city 40 years earlier, Gailly entered the London stadium in first place, but was exhausted and running very slowly.

South African Johannes Coleman, who finished 4th in this race, had placed 6th in the last Olympic marathon in Berlin twelve years earlier.

Returning runners from the pre-war 1936 marathon included sixth-place finisher Johannes Coleman of South Africa.

There was no clear favorite, though Viljo Heino (world record holder in the 10,000 metres) "was considered someone to watch" as he made his marathon debut.

The United States made its 11th appearance, the only nation to have competed in each Olympic marathon to that point.