The Manor was most likely founded in 1515. At that moment, landlords of the Manor owned 615 ha of agricultural land and 2,234 ha of lands with peasants. The first landlord of the Ilzenberg Manor was considered Berndt Kerssenbrock. His family owned the Manor from 1515 to 1616. On Bernd’s death (presumed date of death - 1616.), the manor was inherited by his wife Anna who died in 1680. Afterwards, landlords of the Ilzenberg Manor changed a few times, while Anna lived on somewhere beside and was buried between the Ilzenberg and Alksniai manors. The rule of Kerssenbrock family in the Ilzenberg Manor is considered as having come to an end in 1616.