Asparuh’s successor, Tervel (675–721), was one of the most highly respected rulers not only in the Balkans, but throughout the ancient world.

He was a Christian, like his grandfather Kubrat. With his support, in 705, the Byzantine Emperor Justinian II, who had escaped from exile in Cherson, succeeded in regaining his throne and proclaimed Tervel “Caesar” of Zagore (present-day Stara Zagora region) and other Byzantine territories.

Chroniclers recount how the Emperor ordered the Bulgarian ruler to place his shield on the ground and plant his whip beside it, after which the imperial treasurers poured out so much gold and so many precious objects upon them that they were completely covered.

Three years later, however, the Emperor broke his word, attacked the Bulgarians and suffered a crushing defeat at the Battle of Anchialus (present-day Pomorie).

Tervel’s greatest achievement, however, was the assistance he gave Byzantium during the Arab siege of Constantinople in 717–718. For this reason, the sculpture symbolically depicts him with an Arab helmet beneath his foot. The Bulgarian forces succeeded in holding the enormous Islamic army outside the city walls. Unable to withstand the harsh winter, many of the besiegers died from disease and starvation.

At dawn on 15 August 718, the Bulgarian cavalry surprised the enemy from the rear and killed more than 22,000 Arab soldiers. The survivors fled in panic. Thus, Tervel succeeded in halting the Islamic advance and became known as the “Saviour of Europe”, while the Church canonised him as a saint.

He ruled Bulgaria for 20 years (701–721).