Calendar. David Ewing Duncan.

Calendar
by David Ewing Duncan.
Avon Books: 1998

Subtitled "Humanity's Epic Struggle to Determine a True and Accurate Year", this book mainly focuses on the Gregorian calendar, mentioning non-western developments only as side notes or when they have something to do with Europe.

The book devotes equal time to two aspects: the technological/scientific advances -- and retreats -- in figuring out the length of the year, and the political/social intricacies in developing an accurate and universal calendar.

We quickly reach 100-300 AD at which point the book is an interesting history of the Catholic Church, with an episode in the Middle East. What was most surprising to me is how the most vital aspect of calendar-keeping to the Europeans was the keeping of saints' days -- the commercial and personal aspects were not that important (and were still frequently tied to seasonal time), especially compared with the struggle to accurately determine when to celebrate Easter! Good book.