As he had by the aid to Bulgaria, renounced Byzantine rule, he looked to the west, seeing potential in an alliance with the Pope.
It most likely took place during Uroš' captivity in Byzantium, where he had been sent as a hostage by his uncle Vukan following the capture of Lipljan in 1094 by the troops of Alexios I Komnenos.
He married a daughter of Vukan, the Grand Prince of Serbia (in Raška), thereby ending the civil war between the two polities of Duklja and Raška, with a peace lasting 12 years.