17th Century Chinese Book Identified in Christ Church Library Collections

A Chinese printed book in Christ Church library has been recently identified as an exciting 17th century calendar produced in Taiwan at the time of an extraordinary episode in Chinese and Taiwanese history.
The book's title translates roughly as The Imperial Calendar of the Twenty-Fifth Year of the Yongli Emperor of the Great Ming, the year of Xinhai. The titular emperor, however, does not appear on any conventional list of emperors of the Ming dynasty (1368-1644), nor was he even alive at the time of the publication of the calendar.  
Detail from 17th century Ming CalendarThe Yongli Emperor (full name Zhu Youlang) was a dissident prince of the Ming royal line who had retained an area of the southern Chinese coast long after the Manchu banner armies had marched into China and taken control of Beijing, founding the Qing dynasty (1644-1911). Part of a series of Ming princes that held out against the Qing army in mountainous South China as part of the Southern Ming dynasty, the Yongli Emperor ruled for two decades with the support of the maritime commander Zheng Chenggong, known to Western literature as "Coxinga". After the Yongli Emperor's eventual demise at the hands of the Manchus in 1659, Zheng retreated to Taiwan, where he founded an independent state maintaining all the trappings of a civil apparatus subordinated to the Ming dynasty, save for the existence of an actual Ming monarch.
The production of calendars such as the Christ Church copy had always been a prerogative of the central Chinese government of great symbolic importance. One of the earliest books to be printed in Taiwan, the calendars were published by Coxinga's son , Zheng Jing, using the reign title of the defunct Yongli Emperor to bolster the legitimacy of his dissident regime.
The book is bound in traditional Chinese fashion, with pages consisting of large sheets printed on one side and folded in half so that text appears on both sides. The books are woodblock-printed in indigo, which according to Frances Wood was used as a sign of mourning for the fall of the Ming dynasty.
Currently bound in 18th century Western bindings, the book could have been part of the 50 copies of the same title sent by Zheng Jing as a gift to Henry Dacres, the East India Company's agent in Bantam. The calendars were objects of fascination for European intellectuals such as Elias Ashmole and Robert Boyle, who vaguely realised the books' connection to astrology.
For more information, see the fully digitized volume hosted on Digital.Bodleian and David Helliwell (Bodleian Library Curator of Chinese Collections) on the Southern Ming calendars.

Many thanks to Alexandra Nachescu (Oxford University BA in Sinology and finalizing an MA in Chinese Art at SOAS, London) for identifying the book.