Jakob Kettler was a notable figure in the 17th century, known for his role as the Duke of Courland. He ruled from 1642 until his death in 1682 and is recognized for his efforts to develop the economy and trade in his duchy. Kettler sought to establish Courland as a significant player in the Baltic region. Under his leadership, Courland expanded its overseas trade, particularly in the West Indies and North America. Kettler also promoted the establishment of colonies, which contributed to the duchy's wealth and influence during his reign. His legacy includes the growth of Courland as a maritime power.