Æthelberht (/ˈæθəlbərt/; also Æthelbert, Aethelberht, Aethelbert or Ethelbert; Old English: Æðelberht [ˈæðelberˠxt]; c. 550 – 24 February 616) was King of Kent from about 589 until his death. The eighth-century monk Bede, in his Ecclesiastical History of the English People, lists him as the third king to hold imperium over other Anglo-Saxon kingdoms. In the late ninth century Anglo-Saxon Chronicle, he is referred to as a bretwalda, or "Britain-ruler". He was the first Anglo-Saxon king to convert to Christianity.
Æthelberht was the son of Eormenric, succeeding him as king, according to the Chronicle. He married Bertha, the Christian daughter of Charibert I, king of the Franks, thus building an alliance with the most powerful state in contemporary Western Europe; the marriage probably took place before he came to the throne. Bertha's influence may have led to Pope Gregory I's decision to send Augustine as a missionary from Rome. Augustine landed on the Isle of Thanet in east Kent in 597. Shortly thereafter, Æthelberht converted to Christianity, churches were established, and wider-scale conversion to Christianity began in the kingdom. He provided the new church with land in Canterbury, thus helping to establish one of the foundation stones of English Christianity.
Æthelberht's law for Kent, the earliest written code in any Germanic language, instituted a complex system of fines; the law code is preserved in the Textus Roffensis. Kent was rich, with strong trade ties to the Continent, and Æthelberht may have instituted royal control over trade. Coinage probably began circulating in Kent during his reign for the first time since the Anglo-Saxon settlement. He later came to be regarded as a saint for his role in establishing Christianity among the Anglo-Saxons. His feast day was originally 24 February but was changed to 25 February.
