Pomerania-Stargard was ruled by two brothers, Bogislaw VIII and Barnim V, who inherited the lands from Casimir.

In 1386, Bogislaw VIII and his brother Wartislaw VII signed an alliance with the State of the Teutonic Order, hoping to reclaim the lands that belonged to the previous duke, Casimir IV.

In 1395, Bogislaw VIII allied with Władysław II Jagiełło, and in 1403, he became his courtier, pledging his alliance to Poland, in case of war against the Teutonic Order.

[1][2][3] In 1395, after the death of Wartislaw VII (older brother of Stargard dukes), they inherited Pomerania-Stolp, making the personal union between two states.

In the exchange, he received Lauenburg and Bütow Land as well as Człuchów, Biały Bór, Debrzno, Świdwin and Czarne.