The Christian calendar was originally based on the Julian calendar of the Romans.

公历最初是基于罗马的儒略历的。

《柯林斯英汉双解大词典》

By then the Julian calendar was out of sync with the seasons by 11 days.

那时儒略历对季节的偏差已到了11天。

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By 1582 the Julian calendar was out of sync with the seasons by several days.

到1582年，儒略历日期对季节出现了数天的不同步。

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Orthodox Christmas is observed on January seventh, based on the Julian calendar.

VOA: special.2009.12.21

However,the Orthodox Church in America says most of its members follow the revised Julian calendar and celebrate on December twenty-fifth.

VOA: special.2009.12.21

In 1918, in the Soviet Union, January 31 under the Julian Calendar system was the last day of its use.

CNN: Saturday,

Before the Revolution, Russia had not yet adopted the Gregorian calendar, introduced by Pope Gregory XIII in 1582 to mitigate the errors of the Julian calendar, which owes its name to the Roman emperor who had chosen it 46 years before the birth of Jesus Christ.

UNESCO: International Women��s Day: why the 8 of March?

Typical Belarusian New Year celebrations take place according to the 'old' Julian style calendar and are combined with distinctive local performing arts.

UNESCO: Culture