In 1015 Bulgaria was brought to subjection. A new state of things began for the Bulgarians, who till then had never felt the control of an enemy. The people longed for liberty, and there were many attempts at revolt. Towards 1186, two brothers, John and Peter Assen, raised a revolt and succeeded in re-establishing the ancient kingdom, choosing as capital Tirnova, their native town. It was then that Tirnova became what it still remains, the historic town of Bulgaria. The reign of John and Peter Assen was a brilliant time for Bulgaria. Art and literature flourished as never before, and commerce developed to a considerable extent. Once more the Bulgarian Empire was respected and feared abroad. But this Bulgarian Empire was doomed to as short a life as its predecessor, though for a brief while it held out the illusionary hope of permanency. Bulgaria, from the Danube to the Rhodope Mountains, was won from the Greeks, and John Assen was powerful enough to dream of entering into alliance with the Emperor Frederick Barbarossa. An assassin's sword, however, ended John Assen's life prematurely. He was followed on the throne by his brother Peter. He, too, was assassinated, and was succeeded by his brother Kalojan, who had all the warlike virtues of John Assen, and re-established the Bulgarian Empire with territories which embraced more than half the whole Balkan Peninsula. Seeking to add to the reality of power some validity of title, Kalojan entered into negotiations with the Pope of Rome, made his submission to the Roman Church, and was crowned by a Papal nuncio as king. It was about this time that Constantinople was captured by the Crusaders, and Count Baldwin of Flanders ascended the throne of the Caesars. The Greeks, driven from their capital but still holding some territory, made an alliance with Kalojan, and once again Greek and Bulgar fought side by side, defeating the Franks and taking the Emperor Baldwin prisoner. Then the alliance ended--never, it seems, can Bulgar and Greek be long at peace--and a war raged between the Greek Empire and Bulgaria, until in 1207 Kalojan was assassinated. A brief period of prosperity continued for Bulgaria while John Assen II. was on the throne. He was the most civilised and humane of all the rulers of ancient Bulgaria, and there is no stain of a massacre or a murder remembered against his name. He made wars reluctantly, but always successfully. An inscription in a church at Tirnova records his prowess: