All through his running career, Henry Eriksson was overshadowed by his fellow countryman Lennart Strand, except in only and most important occasion at the LondonOlympic Games.
Eriksson made his first international appearance at the 1946 European Championships in Oslo, finishing second in 1500 m, behind Strand. On July 15, 1947, in the Swedish National Championships at Malmö, Eriksson and Strand had a very close 1500 m race, which Strand won with a new world record of 3:43.0. Eriksson was second in time of 3:44.4, and that would remain his personal best in that distance.
At London, the main favourites to the 1500 m Olympic gold were Swedes Strand, Eriksson and Gösta Bergkvist. In the Olympic final the conditions were perhaps not the best. The race itself started in heavy rain and on a sodden track. After one kilometer, Eriksson and Strand picked up the speed and swept past the rest of the field. With 400 m to go they were 15 yards (14 m) ahead of Wim Slijkhuis of Netherlands. Coming out of the last curve, Strand tried to pass Eriksson but didn't manage to get past his rival. Eriksson was a good four yards clear to win in 3:49.8.