Rockingham was launched in America in 1767 as Almsbury. By 1768 Samuel Enderby & Sons were her owners and her name was Rockingham. From 1775 Enderbys were using her as a whaler, and she made eight whaling voyages for them under that name. In 1782 Enderbys renamed her Swift, and as Swift she then performed ten whaling voyages on the Brazil Banks and off Africa until through 1793. She was still listed in Lloyd's Register as whaling until 1795.