Arnulf, also known as Arnoud or Arnold, succeeded his father in 988 as Count of Frisia, which by around AD 1100 would come to be referred to as the county of Holland.
Arnulf was the first count to come into conflict with the West Frisians and in 993 he invaded deep into their territory, but on 18 September of that year he was defeated and killed in a battle near Winkel in West-Friesland.
His son Dirk was still a boy at this time, but Arnulf's widow Luitgard managed to retain the county for her son with support from first Emperor Otto III and later her brother-in-law, Emperor Henry II.
The couple had (at least) two sons; the future Count Dirk III and Siegfried (also known as Sicco).
On 20 September 993 Liutgard donated her properties at Rugge to Saint Peter's abbey of Ghent for the soul of her husband.