Louis the Stammerer ( November 1 , 846 â '' April 10 , 879 ; ) , was the oldest son of Charles the Bald and Ermentrude of OrlÃ ans . Louis the Stammerer ( 1 November 846 â `` 10 April 879 ) was the King of Aquitaine and later King of West Francia . He was the eldest son of Charles the Bald and Ermentrude of OrlÃ ans .