How did Pope Gregory fix the Julian Calendar?

Answer 1

The Gregorian Calendar was devised both because the mean year in the Julian Calendar was slightly too long, causing the vernal equinox to slowly drift backwards in the calendar year, and because the lunar calendar used to compute the date of Easter had grown conspicuously in error as well.

With love in Christ.

Answer 2

that's how april 1 became april fool's day.
now go look it up. no spoonfeeding for you today..