László Batthyány-Strattmann was born on 28 October 1870, in Dunakiliti, Austria-Hungary, into a very old Hungarian aristocratic family, the sixth of ten brothers. The family moved to Austria in 1876.
His childhood was marred by the fact that his father left his family and converted to Protestantism in order to marry another woman. Ladislaus' mother died when he was twelve years old.