Jakob Lüthi joined the Young Communist League of Switzerland in 1929.
In the communist movement, Jakob's nom de guerre was Tomi.
He travelled back to Switzerland along with an Alsatian woman, Rosel Iltis, whom he married two years later.
[1] Lechleiter became the secretary of the Young Communist League of Switzerland in 1934, a position he held until 1937.
[1] Lechleiter served as the Zurich canton secretary of the Swiss Party of Labour between 1945 and 1956, and as national secretary of the party between 1966 and 1978 (as part of a triumvirate along with Jean Vincent and André Muret).