Background
Johann Jakob was born in Bergnassau, one of three sons of the administrator Simon Moritz Bethmann (1687–1725).
Johann Jakob was born in Bergnassau, one of three sons of the administrator Simon Moritz Bethmann (1687–1725).
While the brothers Johann Philipp and Simon Moritz established the Gebrüder Bethmann bank based on their uncle"s inheritance, Johann Jakob moved to Bordeaux in 1740, where he established Bethmann & Imbert (since 1779 Bethmann & fils) as a trading enterprise and shipowning company. In 1749 he took Swiss citizenship and in 1758 he became a citizen of Frankfurt am Main. In 1768 he was appointed imperial consul for Bordeaux, and in 1776 he was knighted.
Bethmann proved an astute businessman and prospered quickly.
After Johann Jakob"s death in Bordeaux, his Frankfurt grandchildren returned to the city.