text: 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.
  Historical context
  In the fifth century, raids on Britain by continental peoples had developed into full-scale migrations. The newcomers are known to have included Angles, Saxons, Jutes and Frisians, and there is evidence of other groups as well. These groups captured territory in the east and south of England, but at about the end of the fifth century, a British victory at the battle of Mount Badon (Mons Badonicus) halted the Anglo-Saxon advance for fifty years. From about 550, however, the British began to lose ground once more, and within twenty-five years it appears that control of almost all of southern England was in the hands of the invaders.