Gerolf or Gerulf (c. 850 – 895/896) was the second count of this name who is attested in the area of Friesland (which also included Holland at the time). Gerolf's main area of power seems to have been in Kennemerland. Count Gerolf is often regarded as the founder of the County of Holland, although the actual name "Holland" is from a later time. His ancestry is unclear, but he may have been a son or, more likely, a grandson of the earlier Gerolf, who was a count in the area of Frisia at the time of the reign of Emperor Louis the Pious (fl. 833) and who later joined a monastery. The earlier Gerolf died in 855. There is some limited and vague evidence that this earlier Gerolf was a son of a certain Theodoric, who in turn supposedly descended from the Frisian king Redbad (d. 719). Count Gerolf