The Swedish calendar, which is used between March 1, 1700 (March 11, 1700 of the Gregorian calendar, February 29, 1700 according to the Julian calendar), and February 30, 1712 (March 11, 1712 of the Gregorian calendar, February 29, 1712 according to the Julian calendar) was ten days of the Gregorian calendar and a day before the Julian calendar.
In November 1699 it was decided that Sweden would gradually adopt the new style (what it called the Gregorian calendar to avoid reference to the popes), beginning in 1700. The process would go to so that took away one day a year for eleven years. (Some sources say that the plan was to skip all leap days in the period from 1700 to 1740, to thus gradually approaching the Gregorian Calendar over a period of 40 years.) The plan skippades leap day in 1700, but in the following years were not more days away.
In January 1711 decided the king, Charles XII, Sweden to give up and go back to the old style (Julian calendar). An extra day was placed at 30 February 1712 and thus came Sweden the following day, March 1, 1712, again in phase with the Julian calendar.
First, in 1753, Sweden would switch to the Gregorian calendar, February 17 was followed by March 1. Despite this, Sweden did not adopt until 1844 the Gregorian rules for determining when Easter should fall.
© Genney