Some colonial territories for the Duchy of Courland and Semigallia were acquired by its third Duke and Gotthard's grandson Jacob Kettler. In his youth and during his studies abroad he was inspired by the wealth being brought back to various western European countries from their colonies. As a result, Kettler established one of the largest merchant fleets in Europe, with its main harbours in Windau (today Ventspils), and Libau (today Liepāja). The Commonwealth never concerned itself with the Duchy of Courland's colonial aspirations, even though in 1647 Kettler met with king Władysław IV Waza, and suggested creation of a joint trade company, which would be active in India. However, the ailing king was not interested, and Kettler decided to act on his own.
