[1] In 1899 Marin visited Greece, Poland, Russia, Scandinavia, Armenia, Turkestan, Central Asia and Western China.

In all his travels Marin wanted to apply the concepts of Pierre Guillaume Frédéric le Play and the Ecole d'économie sociale in studying societies.

[1] In 1903 Marin was one of the founding members of the Republican Federation (Fédération républicaine), the largest conservative party during the French Third Republic.

He was Minister of Health and Physical Education from 9 February 1934 to 8 November 1934 in the cabinet of Gaston Doumergue.

[1] Marin was again Minister of State from 10 May 1940 to 16 June 1940 - the crucial period beginning with the German invasion of the Low Countries and ending with defeat in the Battle of France.

[1] Marin refused to take part in the vote on 10 July 1940 that gave full powers to Marshal Philippe Pétain[citation needed].

He resumed his research and teaching activities, and relaunched La Nation, as a morning paper in which he published long editorials.

After the second constitution was chosen by the Assembly and ratified by plebiscite, he was elected to the first legislature of the French Fourth Republic in November 1946.

He remained active in the academic world and continued to publish works on political or ethnographical subjects.

He was active in numerous scholarly societies and institutions: Publications by Louis Marin include:[3]