section_path: History/Vulgar Era
section_name: Vulgar Era
paragraph_text: Vulgar Era
  
  The term "Common Era" is traced back in English to its appearance as "Vulgar Era" to distinguish years of the Anno Domini era, which was in popular use, from dates of the regnal year (the year of the reign of a sovereign) typically used in national law. (The word 'vulgar' originally meant 'of the ordinary people', with no derogatory associations.)
  
  The first use of the Latin term anno aerae nostrae vulgaris may be in a 1615 book by Johannes Kepler. Kepler uses it again, as ab Anno vulgaris aerae, in a 1616 table of ephemerides, and again, as ab anno vulgaris aerae, in 1617. An English edition of that book from 1635 may contain the earliest known use of "Vulgar Era" in its title page. A 1701 book edited by John Le Clerc includes the phrase "Before Christ according to the Vulgar Æra, 6".
  
  The Merriam-Webster Dictionary gives 1716 as the date of first use of the term "vulgar era" (which it defines as "Christian era").
  
  The first published use of "Christian Era" may be the Latin phrase annus aerae christianae on the title page of a 1584 theology book, De Eucharistica controuersia. In 1649, the Latin phrase annus æræ Christianæ appeared in the title of an English almanac. A 1652 ephemeris may be the first instance of the English use of "Christian Era".
  
  The English phrase "Common Era" appears at least as early as 1708, and in a 1715 book on astronomy, it is used interchangeably with "Christian Era" and "Vulgar Era". A 1759 history book uses common æra in a generic sense to refer to "the common era of the Jews". The phrase "before the common era" may have first appeared in a 1770 work that also uses common era and vulgar era as synonyms in a translation of a book originally written in German. The 1797 edition of the Encyclopædia Britannica uses the terms vulgar era and common era synonymously. In 1835, in his book Living Oracles, Alexander Campbell wrote: "The vulgar Era, or Anno Domini; the fourth year of Jesus Christ, the first of which was but eight days". He refers to the common era as a synonym for vulgar era: "the fact that our Lord was born on the 4th year before the vulgar era, called Anno Domini, thus making (for example) the 42d year from his birth to correspond with the 38th of the common era". The Catholic Encyclopedia (1909), in at least one article, reports all three terms (Christian, Vulgar, Common Era) being commonly understood by the early 20th century.
  
  The phrase "common era", in lower case, also appeared in the 19th century in a "generic" sense, not necessarily to refer to the Christian Era, but to any system of dates in everyday use throughout a civilization. Thus, "the common era of the Jews", "the common era of the Mahometans", "common era of the world", or "the common era of the foundation of Rome". When it did refer to the Christian Era, it was sometimes qualified (e.g., "common era of the Incarnation", "common era of the Nativity", or "common era of the birth of Christ").
  
  An adapted translation of Common Era into Latin as Era Vulgaris was adopted in the 20th century by some followers of Aleister Crowley, and thus the abbreviation "e.v." or "EV" may sometimes be seen as a replacement for AD.