Gabriel Syveton was a French historian and politician. He was one of the founding members of the patriotic and anti-Dreyfus Ligue de la patrie française. He was elected as deputy for the Seine in 1902. He exposed the existence of a card file compiled from Freemason reports on public officials. It listed practicing Catholics, who should be passed over for promotion. He was found dead the day before being required to appear in court after slapping the Minister of War in the Chamber of Deputies.

The Ligue de la patrie française was a French nationalist and anti-Dreyfus organization. It was officially founded in 1899, and brought together leading right-wing artists, scientists and intellectuals. The league fielded candidates in the 1902 national elections, but was relatively unsuccessful. After this it gradually became dormant. Its bulletin ceased publication in 1909.