Simplify the following text for a Grade 6 native English-speaking person.
Original: Rudolph ( also Radulf , Ralph , or Raoul ) ( died 15 January 936 ) was the duke of Burgundy between 921 and 923 and King of France from July 13 , 923 until his death .
Simplified: Rudolph ( also Radulf , Ralph , or Raoul ) ( c. 890 â `` 14\/15 January 936 ) was the Duke of Burgundy between 921 and 923 and King of Western Francia from thereafter to his death .