He was born in Grande-Digue, New Brunswick, the son of Hypolite Léger. He taught school for one year before continuing his education at St. Joseph's College in Memramcook. In 1888, he graduated with an M.D. from the Detroit Medical College. Later that year, he married Élise Michaud. Léger was first elected to the House of Commons in an 1890 by-election held after Pierre-Amand Landry resigned his seat to accept an appointment as judge. He died in office at the age of 26.