Le Braz was sent on foreign cultural missions by the French Government twenty times. He made several visits to the US, Canada and Switzerland, lecturing at Harvard University in 1906, and at Columbia University in 1915. During his 1915 visit he married Henrietta S. Porter of Annapolis, who died in 1919. In 1921 he married Mabel Davison of Manhattan, sister of the famed banker Henry P. Davison. American novelist John Nichols is his great-grandson. He is the maternal great-grandfather of the musician Tina Weymouth and the architect Yann Weymouth along with their six siblings.