Arnulf I, Count of Flanders

Arnulf I, known as "the Great", was the first Count of Flanders, born between 893 and 899. He was the son of Baldwin II of Flanders and Ælfthryth of Wessex, linking him to both the Anglo-Saxon kings of England and Charlemagne. Upon his father's death in 918, Arnulf became Count of Flanders, while his brother Adeloft took the County of Boulogne.

In 933, after Adeloft's death, Arnulf assumed control of Boulogne but later transferred it to his nephew, Arnulf II. He expanded Flemish territory southward, taking regions such as Artois and Ponthieu, and made Bruges a central administrative hub. His conflicts with the Normans led to the murder of William Longsword in 942, and he later focused on reforming the Flemish government.

Arnulf I died on 27 March 964, reportedly murdered by Heluin in revenge for William Longsword's death, and was buried in Saint-Peter's Abbey in Ghent. He was succeeded by his grandson, Arnulf II of Flanders, after his own son Baldwin III predeceased him.