who created the gregorian calendar

The Gregorian calendar was created by Pope Gregory XIII in 1582. He introduced it as a reform of the Julian calendar through the papal bull "Inter gravissimas." The calendar's design was based on the work of an Italian scientist, Aloysius Lilius (also known as Luigi Lilio), who helped develop the leap year system that corrected the Julian calendar's inaccuracies in aligning with the solar year. The reform aimed to bring the date of Easter closer to the spring equinox and correct the calendar's drift from the seasons caused by the Julian calendar's miscalculation of the year's length.