when was the first millennium
The first millennium is a period of time that began on January 1, AD 1, and ended on December 31, AD 1000, of the Julian calendar. It was the first period of one thousand years in the Anno Domini or Common Era. In Europe and the Mediterranean, the first millennium was a time of great transition. The 1st century saw the peak of the Roman Empire, followed by its gradual decline during the period of Late Antiquity, the rise of Christianity and the Great Migrations.