How many years ago is 1520 AD?

1520 AD is 491 years ago, as of 2011.

To calculate how many years ago something was, use this formula:

current year - older date = how many years ago

for example:

how many years ago was 1934 (older date)?

1934 is the older date, and 2011 is the current date so therefore:

2011-1934=77