In the late tenth century there was a brief revival of Bulgarian power under Samuel, when the Bulgarians succeeded in liberating the northeastern sector of the country from Byzantine control and captured southern Macedonia. But the revival was short lived. The Byzantine emperor, Basil II, was determined to regain his lost land and once again recaptured the northeastern sector. In 1014 Basil again invaded Bulgaria; defeated Samuel's army; and, in an act of matchless cruelty, blinded 14,000 Bulgarian soldiers. From 1018 until 1185 all of Bulgaria was under Byzantine rule.
The eleventh and twelfth centuries witnessed a period of extreme hardship for the country. Byzantine domination was harsh and punitive. Monetary taxes, which added to the already heavy burdens of the peasantry, were levied in 1040. Bulgarian feudalism was replaced by Byzantine feudalism. The Byzantine church itself was a vehicle of oppression as it was later to become under Turkish rule; the church owned entire estates and villages and the people who inhabited them. There were a series of revolts during the eleventh century, but none were successful in overthrowing Byzantine tyranny. During this period the first and second crusades made their way through the Balkan Peninsula, wreaking havoc among the local populations.
The Second Bulgarian Kingdom was established in 1186 and lasted until 1396, when—like the First Bulgarian Kingdom—it was conquered by a powerful enemy and neighbor. Ironically, history came full circle to spell defeat for the Bulgarians. In the twelfth century, when the Byzantine Empire was declining because of internal weakness, the Bulgarians were able to free themselves from domination. In the fourteenth century, when Bulgaria itself was weakened by domestic strife, it was conquered by an enemy whose oppression was greater than that of the Byzantine Empire: the Ottoman Turks.
At the close of the twelfth century the internal situation in Bulgaria was deteriorating. Taxes had been increased, and the burden borne by the peasants became still heavier. The feudal lords openly began to proclaim their independence from Byzantium, whose empire was by now steadily declining. Bulgaria was surrounded by its enemies: the Ottoman Turks, the Magyars, and the Normans. In 1183 the Magyars invaded, penetrating as far as Sofia. Realizing the vulnerability of the Byzantine Empire, the Bulgarians rebelled under the leadership of two brothers, Asen and Peter. The brothers first liberated northeastern Bulgaria and then proceeded into Thrace, where they were opposed by Isaac Angel, then emperor of Byzantium. In 1187 a peace treaty was concluded in which Byzantium conceded autonomy to Bulgaria.
Despite the peace treaty, however, the Bulgarians continued to wage war against the empire, hoping to regain northern Bulgaria and Macedonia—a contested territory and bitterly disputed issue throughout Bulgarian history. In 1201 the empire again concluded a peace treaty with the Bulgarians, ceding all of northern Bulgaria and a large part of Macedonia. Eventually, in 1207 Constantinople recognized the complete independence of Bulgaria, and Bulgarian freedom was firmly established.
This new-found independence, however, did not extend to the Bulgarian church, which was still under the aegis of the empire. For that reason Kaloyan, the Bulgarian ruler, negotiated with the Roman pope, Innocent III, in order to ally the Bulgarian church with the church of Rome. The motives of Rome and those of Kaloyan were similar: to isolate the influence of Byzantium from Bulgaria. In 1204 Kaloyan was crowned king by the papal nuncio in Turnovo. Although this union lasted only briefly, it served the purpose for which it was designed, and Bulgaria was effectively cut off from Byzantium.
During the thirteenth century the Holy Roman Empire replaced the Byzantine Empire on the borders of Bulgaria, and Byzantine aggression was replaced by that of the Holy Roman Empire. When Rome declared war on Bulgaria, the Bulgarians invaded Thrace, defeating the crusaders at Adrianople in 1205. The reestablishment of the Bulgarian patriarchate in 1235 represented the end of the short-lived alliance between the Bulgarian church and Rome.
Under the reign of Ivan Asen II in the mid-thirteenth century peace was again restored, and the country once more extended its territories. The Bulgarians succeeded in capturing eastern Thrace, the Aegean coast, Albania, and Macedonia. Bulgarian territory at this time was as great as under the reign of Tsar Simeon; with these conquests Bulgaria became the largest state in the Balkans. The country was now surrounded by three seas—the Black Sea, the Aegean Sea, and the Adriatic Sea—opening the country's doors to foreign trade and culture.
Again, as in the time of Simeon, the arts and cultural life of the country flourished. Monasteries, churches, and fortresses were constructed. Religious literature and art achieved a high level of excellence, and secular works became popular. The first chronicle of Bulgarian history was written, and an interest in history grew among the people. The first Bulgarian coins were minted at this time. Trade, particularly with Italy, increased greatly because of Bulgaria's free access to the sea. Merchants and ambassadors came to Bulgaria from abroad, lending their influence to Bulgaria's economic and cultural life.
By the second half of the thirteenth century, however, internal conditions in the country had deteriorated. The feudal system, which had been further consolidated during the thirteenth century, had exacerbated the tensions of the peasants, and hostilities among the boyars increased. The throne was contested between 1257 and 1277 and was eventually taken forcibly by Ivailo, known as the swineherd tsar because of his leadership of a peasant uprising in 1277.