Prince of Pereyaslavl
The Prince of Pereyaslavl was the "kniaz" (the ruler or sub-ruler) of the Rus Principality of Pereyaslavl, a lordship based on the city of Pereyaslavl on the Trubezh river and straddling extensive territory to the east in what are now parts of Ukraine. It lay on Rus civilization's southern frontier with the steppe. The principality emerges was apportioned as the inheritance of Vsevolod Yaroslavich, son of Yaroslav the Wise; his brother Svyatoslav received Chernigov, while Smolensk went to Vyacheslav and Vladimir-in-Volhynia to Igor; this ladder of succession is related to the seniority order  mentioned above. Vsevolod's appanage included the northern lands of Rostov and the lightly colonised north-eastern zone of Rus (see Vladimir-Suzdal). The "Primary Chronicle" recorded that in 988 Vladimir had assigned the northern lands (later associated with Pereyaslavl) to Yaroslav. The town was destroyed by the Mongols in March 1239, the first of the great Rus cities to fall. Certainly from the reign of Vsevolod Yaroslavich, the princes of Pereyaslavl held the principality of Rostov-Suzdal, which was heavily colonized by Slavs thereafter, a process which strengthened the region's power and independence, separating the two regions. In  1132, Yaropolk became Grand Prince on his brother Mstislav's death, while the Monomashichi descended into general internecine conflict over the Pereyaslavl principality. Yaropolk appointed Vsevolod Mstislavich, prince of Novgorod, to the principality of Pereyaslavl - in this era designated heir to the Kievan throne - thus provoking Yaropolk's younger brother Yuri Dolgoruki, controller of Suzdal, into war. Yuri drove out Vsevolod, whom Yaropolk then replaced with Izyaslav. An agreement was reached by 1134 between Yuri and Yaropolk that their common brother Vyacheslav would take the throne of Pereyaslavl.