Nicolai Benjamin Aall was born at
Porsgrund, Norway, the first son of Niels Jacobsen Aall (1702–1784) and Benedicte Henrikke Bergh (1714–1748). Niels Jacobsen Aall was a lumber merchant and shipowner who had been born in
London. He moved to
Porsgrund in 1712. Benedicte Henrikke was from
Moss and was the second of three wives. At nine years old Nicolai Benjamin lost his mother, but five years later his father married Fredrikke Sophie Rasch (1726–1760). Nicolai Benjamin's younger half-brother Jacob Aall (1754–1826) became a noted wholesaler, whereas his youngest half-sister Benedicta Henrikka Aall (1756–1813) married Severin Løvenskiold (1743–1818). Their son,
Severin Løvenskiold (1777–1856) was his nephew.{{cite web|url=https://lokalhistoriewiki.no/index.php/Severin_L%C3%B8venskiold_(1777%E2%80%931856) |title =Severin Løvenskiold (1777–1856)|website= lokalhistoriewiki.no ==Career==