First Warsaw Pact Military Exercise

The first war against Swantopolk II was a military conflict in Pomerelia and Kuyavia.^¹ It was fought between 1236 and 1238 by the Duchy of Lubiszewo, and later the Mecklenburgian forces, both led by Sambor II, the Duchy of Białogarda, led by Ratibor and the Duchy of Kuyavia, led by Casimir I, all fighting against Duchy of Gdańsk, led by Swantopolk II.^¹ The conflict ended with the conquest of Lubiszwo and Białogarda, and subsequent recovery of control over their rulers by Swantopolk II.^¹ Additionally, Kuyavia conquered neighboring lands of the Duchy of Gdańsk, and was subsequently raided by it, receiving heavy financial and material losses.^¹ Following the war, Swietopelk II was excommunicated by the Catholic Church.^¹