This chapter shows that during the eleventh and twelfth centuries the Croats were never unified under a strong central government. They lived in different areas: Pannonian Croatia, Dalmatian Croatia, and Bosnia, which were more frequently controlled by agents of Byzantium, Venice and Hungary. In 1036, Jaroslav's victory over the Petcheneks secured safe passage for merchants travelling from Kiev to Constantinople. Jaroslav's reign was one of the high points in the history of Rus' and his achievements earned for him the sobriquet the Wise'. He helped to lay the foundation for a codified law by issuing 'The Russian Law. During most of the eleventh and twelfth centuries Bulgaria experienced the period of Byzantine rule. In 1018 when Basil II conquered Bulgaria a number of Serbian principalities also fell under Byzantine rule. Although the Latin Christians were affiliated to Rome they continued to celebrate the liturgy in the Slavonic language even after its use had been condemned by the synod.