Nicod was a supporter of the French Section of the Workers' International (SFIO); he became the party's secretary for the department of Ain in 1912.

At the Tours Congress in December 1920, Nicod became a founding member of the French Communist Party (PCF) although he did not accept all of the Twenty-one Conditions.

In 1927, Nicod travelled to the Soviet Union; upon his return wrote a number of articles about the successes and problems of the young state.

After France fell to German invasion in 1940, Nicod was one of The Eighty who voted against dissolving French democracy and giving dictatorial powers to Philippe Pétain.

[3] As a result, he was imprisoned in an internment camp in Évaux-les-Bains until he was freed by French Forces of the Interior in June 1944.

He was re-elected to the posts he held prior to the war, being elected to the General Council of Ain in 1945, and Mayor of Oyonnax in 1947.