500

It is one of only seven years to use just one Roman numeral. The seven are 1 AD (I), 5 AD (V), 10 AD (X), 50 AD (L), 100 AD (C), 500 AD (D), and 1000 AD (M).

 Events 
Possible date for the Battle of Mons Badonicus: Romano-British and Celts defeat an Anglo-Saxon army that may have been led by the bretwalda Aelle of Sussex (approximate date; suggested dates range from 490 to 510) Note: This battle may have influenced the legend of King Arthur
Possible date at which Fergus I of Dalriada begins his reign
Approximate beginning of the Heptarchy period in the history of England
Approximate year of the founding of the Kingdom of Essex
Emperor Xuanwu of Northern Wei China becomes sovereign of the Northern Wei Dynasty
Uxmal founded (approximate date)
Traders from southern Arabia settle in northern Ethiopia