By the late 9th century Bulgaria extended from the mouth of the Danube to Epirus in the south and Bosnia in the north-west.
Under Peter I and Boris II the country was divided by the egalitarian religious heresy of the Bogomils, and distracted by wars with the Hungarians to the north and the breakaway state of Serbia to the west.
Ivan had a reputation as a wise and humane ruler, and opened relations with the Catholic west, especially Venice and Genoa, to reduce the influence of the Byzantines over his country.
On the death (1207) of his father, Kaloyan, founder of the second Bulgarian empire, the throne was usurped by Ivan's cousin Boril.
Under IvanII the Bulgarian empire reached its zenith, becoming the strongest power in the Balkans; he added Macedonia, Epirus, and much of Albania and Serbia to his lands.
IvanII was succeeded by his sons Kaliman I, who reigned 124146, and Michael, who reigned 124657.