sentences:  Duke Branimir wrote to Pope John VIII affirming this split from Byzantine and commitment to the Roman Papacy.During the solemn divine service in St. Peter's church in Rome in 879, Pope gave his blessing to the duke and the whole Croatian people, about which he informed Branimir in his letters, in which Branimir was recognized as the Duke of the Croats ("Dux Chroatorum").During his reign, Croatia retained its sovereignty from both Holy Roman imperial and Byzantine rule, and became a fully recognized state.