Assassination of William I of Normandy.
William Longsword (French: Guillaume Longue-Épée, Latin: Willermus Longa Spata, Old Norse: Vilhjálmr Langaspjót; c. 893 – 17 December 942) was the second ruler of Normandy, from 927 until his assassination in 942.He is sometimes anachronistically dubbed "duke of Normandy", even though the title duke (dux) did not come into common usage until the 11th century. Longsword was known at the time as count (Latin comes) of Rouen.Flodoard—always detailed about titles—consistently referred to both Rollo and his son William as principes (chieftains) of the Norse.