Assertion: empire's emperor | /r/HasProperty | heraclius
Facets:
Source sentences:
text: The Khazars were in contact with the Persians in the mid-6th century ce, and they aided the Byzantine emperor Heraclius (reigned 610–641) in his campaign against the Persians.
text: This epic victory restored the Danube frontier, which had not been held since the days of the emperor Heraclius.