Jolliver Grimjaw was a sullen, suspicious, and humorless individual. Grimjaw had little patience for administration, asking very direct questions.
Grimjaw and his men traded with some smugglers and led attacks on river boats that refused to pay protection money. They also actively recruited thugs and monsters to join the Cult.
In 1491 DR, Grimjaw and his minions posed as mercenaries and occupied the Rivergard Keep. Soon after, however, some adventurers infiltrated the keep and in the end confronted and defeated Grimjaw.