Izyaslav sent Yaropolk to Rome to request aid from Pope Gregory VII. It is likely that while there Yaropolk made complaints about Boleslaw and about the money the latter had formerly seized from Izyaslav, as the pope subsequently issued a request that Boleslaw return it. Pope Gregory addressed a letter to Izyaslav, called "Demetrius", "King of the Russians", and to his "queen" Gertruda. The letter noted that Yaropolk, called "Peter", had given his own as well as his father's fidelity to the pope, and that it had been requested that the "kingdom of the Ruthenians" be held of St Peter. Two papal legates were sent to Izyaslav, and Izyaslav was urged to give them his full co-operation. It was only after Svyatoslav's death in late 1076 that Izyaslav was able to recover the status of Grand Prince. Vsevolod, who had previously fought against him, was appointed Prince of Chernigov and thus heir to the Kievan throne, explaining perhaps Vsevolod's lack of opposition. The Poles were persuaded by the papacy to give Izyaslav assistance recovering his kingdom, and on July 15, 1077, Izyaslav re-entered Kiev. Yaropolk is found aiding his father and his uncle Vsevolod in 1078, when Oleg Svyatoslavich (and his brother Boris) attempted to gain the throne of Chernigov from Vsevolod. Oleg had been allied to the Polovtsy, and with their help defeated Vsevolod in battle. Grand Prince Izyaslav and Yaropolk, as well as Vsevolod's son Vladimir Monomakh, were able to reverse this result, and Oleg was forced to retreat to Tmutorokan. Grand Prince Izyaslav, Yaropolk's father, died as a result of the battle. The "Primary Chronicle" records that in 1078 before the death of Izyaslav, Yaropolk was "ruling in Vyshhorod", a city north of Kiev, while his brother Svyatopolk ruled as Prince of Novgorod, and Vladimir Monomakh ruled as Prince of Smolensk. After his uncle Vsevolod had become Grand Prince, Yaropolk was given Vladimir-in-Volhynia and Turov, while Monomakh received Chernigov.