refined) coin for the purpose. By 1109, he had managed to restore order by working out a proper rate of exchange for the whole coinage. His new hyperpyron would be the standard Byzantine coin for the next two hundred years. The final years of Alexios's reign were marked by persecution of the followers of the Paulician and Bogomil heresies—one of his last acts was to burn at the stake the Bogomil leader, Basil the Physician, with whom he had engaged in a theological controversy; by renewed struggles with the Turks (1110–1117); and by anxieties as to the succession, which his wife Irene wished to alter in favour of her daughter Anna's husband Nikephorus Bryennios, for whose benefit the special title panhypersebastos ("honored above all") was created. This intrigue disturbed even his dying hours. Nevertheless, despite the unpopularity of some of his measures, Alexios's efforts had been vital to the survival of the empire. Financially and militarily bankrupt, and facing wave after wave of foreign invasion, the empire he inherited had been on the point of collapse. His long struggle to protect and restore the strength of the empire had been exhausting, but Alexios's successors inherited a viable state with both the internal stability and the military restoration but also a lot of financial resources, to expand in the future. Restoration under John II Komnenos Alexios's son John II Komnenos succeeded him in 1118, and was to rule until 1143. On account of his mild and just reign, he has been called the Byzantine Marcus Aurelius. John was unusual for his lack of cruelty—despite his long reign, he never had anyone killed or blinded. He was loved by his subjects, who gave him the name 'John the Good'. He was also an energetic campaigner, spending much of his life in army camps and personally supervising sieges. During John's reign, Byzantium faced many difficulties: enemies confronted the empire on all sides. An invasion of nomadic horsemen from the north threatened Byzantine control in the Balkans, and the Turks were harassing Byzantine territory in Asia Minor. However, John soon proved himself just as determined and energetic as his predecessor. At the Battle of Beroia, John personally led the imperial armies against the Pecheneg invaders. With the aid of the emperor's elite troops, the Varangian Guard, the tribal horsemen were decisively crushed. The emperor's victory was so emphatic that the Pechenegs soon disappeared as