Louis I (German: Ludwig; 23 December 1173 – 15 September 1231), called the Kelheimer or of Kelheim, since he was born and died at Kelheim, was the Duke of Bavaria from 1183 and Count Palatine of the Rhine from 1214. He was a son of Otto I and his wife Agnes of Loon. Louis was married to Ludmilla, a daughter of Duke Frederick of Bohemia.