|William Longsword was the son of Rollo, in the 930s he
emerged from obscurity because of
his war with Arnulf of Flanders, and his support for King
Louis IV (d’Outremer). In December 942 Arnulf called
for a peace conference with William; there, William was murdered.
Arnulf is said to have arranged the assassination
of William Longsword|
(BNF, FR 2813) Grandes Chroniques de France