Duke Jacob of Courland was a ruler of the Duchy of Courland and Zemgale for 40 years (1642-1682).  There were great changes during his rule, with the ship building industry developing rapidly, the first factories appearing, and agricultural output improving.  The duke had a large fleet that brought grain, meat, butter, wool, timber and all that was manufactured at baronial estates in Zemgale and Courland to Western Europe.  The fleet was so big and strong that its ships sailed not just to Europe, but also all the way to Tobago and Gambia, where colonies were established to bring sugar, coffee and spices to Europe.