The first century AD
The sixth century AD covers the years from 501 AD to 600 AD.
The first century.
Any year between 1501 AD and 1600 AD - including 1537 - is in the sixteenth century.
The year 800, as with any year between 701 and 800, fell in the eighth century.
The 2nd century AD.
The first century AD
This is a year in the 13th century AD.
The year 705 AD is in the 7th century.
The sixth century AD covers the years from 501 AD to 600 AD.
1150 AD is in the 12th century.
Both. It was the last year of the 21st century BC, and the first year of the 21st century AD.
1000 AD
any year after AD 800 and before AD 901
any year after AD 800 and before AD 901
The 17th Century AD
6th century AD