Russian calendar data

[Chris Carrier]

Some Russian information of interest to the list, and a question.
 
We have Russia adopting a five-day calendar week in 1929 and a six-day week in
1932.  The exact date for the adoption of the five day week was 1929-10-01 and
for the six day week, 1931-12-01, not 1932.  The 1940-06-27 date for the re-
adoption of the seven day week is accurate; however they re-adopted their
version of the Gregorian Calendar several years earlier (slightly different from ours in how it
handles leap centuries; in the Gregorian, leap centuries are in those years
divisible by 400; in their system, leap centuries are those in years divisible
by either 200 or 600 mod 900, which makes the two calendars even until 2800-
02-28, when we have a leap year and they do not).  The six day week was not
always six days, but an integral part of the month; the usual days off were
the 6th, 12th, 18th, 24th and 30th of the month.  (Source: Evitiar Zerubavel,
THE SEVEN DAY CIRCLE, a book about the history of the week.)
 
Question: we have Greece on the Gregorian Calendar in 1846.  I thought they
were the last holdout, not adopting the Gregorian Calendar until 1923, which
is when the Eastern Orthodox Churches got together and adopted the mod-900
version of the Gregorian Calendar described above.  (The transition was made
by making the day after 1923-09-30 Julian 1923-10-14 Gregorian.)
 
Chris Carrier