The mountain up to the end of the II World War was on the Franco-Italian border. Due to its prominent position overlooking the Col de Montgenèvre, from Louis XIV times till to the ligne Maginot, the area vas heavily fortified. On 23-6-1940 an Italian offensive conquered the mountain and also in 1944 it was the theater of heavy fights between German-Italian and French-Moroccan troops; and after many decades it is still possible to find howitzer chippings on the ground. After the end of the war, following the Paris Peace Treaties signed on February 1947, the border was modified and Mount Chenaillet is now totally in France..