# Note:
William I, "Longsword", b. ca. 891 probably Rouen, c. 927 succeeded to Duchy of Normandy, c. 930 the Bretons rebelled, he subdued them, taking Brittany, the Channel Islands, the Contentin, and the Averanchin; killed in treacherous ambush 17 Dec 942 by servants of Theobald of Blois and Arnulf of Flanders. He m. (1) (Danish wife) Sprota, a Breton; m. (2) Luitgarde de Vermandois, n.i. [no issue], killed 942 by Louis, son of Charles III "the Simple", daughter of Herbert II, Count of Vermandois and Troyes. [Ancestral Roots]
Note: There is an apparent error in Luitgarde's death date of 942. See notes under her. I think the clause ",killed 942 by Louis, son of Charles III "the simple" belongs to William's death and not to Luitgarde's, even though she is the subject of the sentence before & after the clause. I am going to remove the death date as a sourced alternative. It is an obvious error.
# Note: Assassinated by Arnulf/Arnulph/Arnoul "The Old", Count of Flanders, in 942, according to Encyclopaedia Britannica, 1961 ed., Vol. 16, pg. 493, Article: NORMANDY