[1] Platten began his political career as a member of the Social Democratic Party of Switzerland, of which he was secretary between 1915 and 1919.

[2][1] In 1921, along with other dissidents from the left-wing of the Social Democrats, Platten was one of the founding members of the Communist Party of Switzerland.

Fritz Platten is mostly known for having been the main organizer of Lenin’s return trip from exile in Switzerland back home to Russia after the February Revolution.

Due to the First World War, the trip was not easily arranged, but Lenin and his company traveled through Germany in a sealed train car.

They then took the ferry to Sweden and were greeted in Stockholm by the Swedish communist leaders Otto Grimlund, Ture Nerman, Carl Lindhagen and Fredrik Ström, who together with Platten had helped plan the trip.