1600 up to 1650

At the end of the agricultural boom the increasingly self-sufficient knightly economies to the east of the Elbe ousted the peasant economies.

The second major territorial partition in 1621 divided the state into Mecklenburg-Schwerin and Mecklenburg-Güstrow. The Thirty Years‘ War (1618-1648) desolated the country. The siege of small towns and billeting of soldiers lead to the ruin of small tradesmen and merchants. The rural population regularly became victims of marauding soldiers and groups.

The state was conquered by the imperial general Albrecht von Wallenstein in 1628. He was elevated by the Emperor to Duke of Mecklenburg who reported directly to the Emperor. Yet after his murder his approaches to reform were withdrawn. In 1648 Wismar with the island of Poel and the administrative town of Neukloster fell to Sweden.

The war stunted progress in arts and sciences. It led to a brutalisation of conventions. There was an increase in superstition and denunciations due to witchcraft and wizardry.

A period of development in the agrarian economy culminates in a dichotomy between the farming situation to the east and the west of the river Elbe. The gentry largely produces to satisfy its own needs, displacing the local farming community. Farmers experience a sharp decline in their status, until they are finally coerced into serfdom. The 'Farmers and Shepherds Ordinance' of 1616 in Pomerania-Wolgast brings this process to its natural conclusion. Pomerania-Stettin follows suit.

Bogislaw XIV (1580–1637) reunites the duchy with Pomerania-Wolgast in 1625.

The Thirty Years' War (1618–1648) ravages the country. Plague decimates the population in 1624, especially in Pomerania-Stettin. Morals collapse as the war rages. There is an increase in superstition and denunciations for witchcraft and sorcery. The rural population in particular became victims of marauding soldiers and groups.

Albrecht von Wallenstein fails in his first attempt to take Stralsund in 1628. King Gustav II Adolf of Sweden lands on Usedom in 1630 and occupies Stettin, where he forges an alliance with Duke Bogislaw XIV, Prince of Pomerania. Gustav II Adolf had entire forests cleared for building palisades and fire purposes for his troops' camps. Landscapes are flattened to clear the line of fire.

The age of the Pomeranian dukes comes to an end in 1637. This leads to rivalry between Sweden and Brandenburg that remains unresolved until the Peace of Westphalia in 1648.

Brandenburg and Sweden divide the country in 1648.