A treaty between King Valdemar II of Denmark and the Teutonic Order, concluded on 7 June 1238 in Stensby near Vordingborg on Sjælland, which transferred the northern part of Estonia to the Danish king.
After the abduction of Valdemar II by his vassal Count Henry of Schwerin in May 1223, Danish power in the Baltic region collapsed. Unable to hold their Estonian provinces, the Danes in 1225 transferred authority to the papal legate William of Modena, but the Order of the Sword Brethren soon took possession. Pope Gregory IX repeatedly tried to persuade the Sword Brethren to relinquish the provinces, and in February 1236 he resolved that they were to cede Reval (mod. Tallinn, Estonia), Jerwia, Harria, and Vironia to the Danish king. Shortly after this, however, the Sword Brethren were annihilated at the battle of Saule, and the remnants of the order were incorporated into the Teutonic Order.
William of Modena was now charged with the task of persuading the Teutonic Order to observe the papal resolution. He met representatives of all parties in Stensby, where the Teutonic Order agreed to hand over Reval, Jer- wia, Harria, and Vironia to the Danish king, who then as “penitence” returned Jerwia to the order. Finally, it was agreed that the Danish king was to retain two-thirds and the order one-third of future conquests. The treaty enabled the Danes and the order to collaborate closely in crusades against Novgorod and Pskov over the next four years and laid the legal foundation for continuing Danish rule in North Estonia.