The Gregorian Reforms were a series of reforms initiated by Pope Gregory VII and the circle he formed in the papal curia, c. 1050–80, which dealt with...

and thus has a leap year every four years without exception. The Gregorian reform shortened the average (calendar) year by 0.0075 days to stop the drift...

was the drift of 21 March from the observed equinox that led to the Gregorian reform of the calendar, to bring them back into line. Easter commemorates...

of Saint Gregory Things named for Pope Gregory VII: The Gregorian Reform, a series of reforms initiated by Pope Gregory VII and the circle he formed in...

"The Civil Reception of the Gregorian Calendar". In Coyne, G. V.; Hoskin, M. A.; O., Pedersen (eds.). The Gregorian Reform of the Calendar: Proceedings...

corrected by the Gregorian reform of 1582. The Gregorian calendar has the same months and month lengths as the Julian calendar, but, in the Gregorian calendar...

the 116th day of the year, but this has never occurred since the Gregorian reforms were implemented. The first time Easter will occur on April 25 in...

year by almost 6 hours. However, this correction is excessive and the Gregorian reform modified the Julian calendar's scheme of leap years as follows: Every...

The adoption of the Gregorian Calendar was an event in the early modern history of most cultures and societies, marking a change from their traditional...

Gregorian change in the solar calendar, if they were applied at 1 January of the Julian calendar instead of the Gregorian calendar as the reformers implemented...