There were two:
The 9th century BCE (commonly thought of as BC) was 900-801 BCE.
The 9th century CE (commonly thought of as AD) was 801-900 AD.
Now, many will tell you that the century begins with the zero year (100, 1000, etc.). Not so. Consider that when you count to ten, you start with one, not zero (as in 1-2-3-4-5-6-7-8-9-10); the same is true with calendars.
801 AD-900 AD
800 to 899
17 centuries. From the last day of the 9th century BCE to the first day of the 9th century AD was just over 1600 years while From the first day of the 9th century BCE to the last day of the 9th century AD was just under 1800 years.
801AD was the first year of the ninth century.
Annals of the Twenty-Ninth Century was created in 1874.
Annals of the Twenty-Ninth Century has 758 pages.
871 is in the 9th century.
the Saluki and Basenji
Britain's monarchy dates from the ninth century.
895 BC is in the 9th century BC.
2801
Algebra
They would be the ninth century, according to useage in English.
At the end of the ninth century neither England nor France had anything remotely resembling democracy.