The Gregorian calendar was 10 days ahead of the Julian calendar until , then 11 days ahead from . With the Gregorian Calendar starting in 1582, and 1600 being evenly divisible by 400, and thus being a leap year under the Gregorian system despite being a century year, this was the first skipped leap year under the Gregorian Calendar. In Sweden, the year started in the Julian calendar and remained so until February 28. Then, by skipping the leap day, the
Swedish calendar was introduced, letting February 28 be followed by March 1, giving the entire year the same pattern as a
common year starting on Monday. This calendar, being 10 days behind the Gregorian and 1 day ahead of the Julian, lasts until
1712.