Jacob Dirckz van Foreest was born 26 June 1556 in Alkmaar, North Holland, Netherlands to Dirk van Foreest (1527-1596) and Maria de Groot (-1557) and died 18 June 1624 Alkmaar, North Holland, Netherlands of unspecified causes. He married Maria van Egmond van de Nijenburg (1558-1632) 30 June 1585 in Egmond-Binnen, North Holland, Netherlands.
Children
| Name | Birth | Death | Joined with |
| Jan van Foreest (1586-1651) | 4 October 1586 Alkmaar, North Holland, Netherlands | 27 October 1651 Hoorn, North Holland, Netherlands | Josina van Segwaert (1585-1657) |