French–Vietnamese relations started as early as the 17th century with the mission of the Jesuit father Alexandre de Rhodes. Various traders would visit Vietnam during the 18th century, until the major involvement of French forces under Pigneau de Béhaine from 1787 to 1789 helped establish the Nguyễn Dynasty. France was heavily involved in Vietnam in the 19th century under the pretext of protecting the work of Catholic missionaries in the country.