[1] Courland and Semigallia was located in present-day Latvia, and had a population of only 200,000, mostly of Latvian and Baltic German ancestry, and was itself a vassal of the Polish–Lithuanian Commonwealth at that time.
In 1651 the Duchy gained its first successful colony in Africa, on St. Andrews Island in the Gambia River and it established Fort Jacob there.
Soon afterwards the Protestant powers felt sufficiently organised and prepared to launch several colonial expeditions against Spanish interests in the Caribbean.
On 20 May 1654, the ship Das Wappen der Herzogin von Kurland ("The Arms of the Duchess of Courland") arrived carrying 45 cannon, 25 officers, 124 Curonian soldiers and 80 families of colonists to occupy Tobago.
While 120 Curonian colonists had come in 1657, the Dutch colony reached a population of 1,200 by the next year, when 500 French Protestant refugees fleeing Catholic persecution joined them.
Goods exported to Europe included sugar, tobacco, coffee, cotton, ginger, indigo, rum, cocoa, tortoise shells, tropical birds and their feathers.
During this period both colonies continued to thrive until they were taken by the more numerous Dutch settlers, who surrounded Fort James and forced Hubert de Beveren, Governor of the Curonians, to surrender.
The island was abandoned except for visiting buccaneers from March 1683 to June 1686, before again being occupied by a collection of scattered Curonians from throughout the Dutch, French, and English West Indies, as well as by fresh settlers from the home country.
In May 1690, shortly after the island was sold by Courland and Semigallia the previous year, the Curonian government permanently left Tobago, and those who remained essentially joined the buccaneers or other Anglo-Dutch colonies.
At the outbreak of the Third Anglo-Dutch War (1672–1674), the colony was captured and looted again by Barbadians, where in 1673 Adrian Lampsins and the late Cornelius' son Jan briefly again retook Tobago, but the island was recaptured by an English Barbadian force under Sir Tobias Bridge from Barbados, and Adrian was killed alongside his nephew when the fort was blown up.
New Courland is finally sold to the British Empire by around 1690 to 1693, where last mention of the colony was a small group of settlers encountered by a Danish ship in 1693.