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The 1752 Calendar Change

The Julian Calendar | The Gregorian Calendar | Double Dating | The Changes of 1752
Which Calendar Is It? | Links | Bibliography  

Today, Americans are used to a calendar with a "year" based the earth's rotation around the sun, with "months" having no relationship to the cycles of the moon and New Years Day falling on January 1.  However, that system was not adopted in England and its colonies until 1752.  The changes implemented that year have created challenges for historians and genealogists working with early colonial records, since it is sometimes hard to determine whether information was entered according to the then-current English calendar or the "New Style" calendar we use today.

Throughout history there have been numerous attempts to convey time in relation to the sun and moon.  Even now the Chinese and Islamic calendars are based on the motion of the moon around the earth, rather than the motion of the earth in relation to the sun, and the Jewish calendar links years to the cycle of the sun and months to the cycle of the moon.

The Julian Calendar
In 45 B.C., Julius Caesar ordered a calendar consisting of twelve months based on a solar year.  This calendar employed a cycle of three years of 365 days, followed by a year of 366 days (leap year).  When first implemented, the "Julian Calendar" also moved the beginning of the year from March 1 to January 1.  However, following the fall of the Roman Empire in the fifth century, the new year was gradually realigned to coincide with Christian festivals until by the seventh century, Christmas Day marked the beginning of the new year in many countries. 

By the ninth century, parts of southern Europe began observing first day of the new year on March 25 to coincide with Annunciation Day (the church holiday nine months prior to Christmas celebrating the Angel Gabriel's revelation to the Virgin Mary that she was to be the mother of the Messiah). The last day of the year was March 24. However, England did not adopt this change in the beginning of the new year until late in the twelfth century.

Because the year began in March, records referring to the "first month" pertain to March; to the second month pertain to April, etc., so that "the 19th of the 12th month" would be February 19.  In fact, in Latin, September means seventh month, October means eighth month, November means ninth month, and December means tenth month.  Use of numbers, rather than names, of months was especially prevalent in Quaker records.

The Gregorian Calendar
During the Middle Ages, it began to became apparent that the Julian leap year formula had overcompensated for the actual length of a solar year, having added an extra day every 128 years.  However, no adjustments were made to compensate.  By 1582, seasonal equinoxes were falling 10 days "too early," and some church holidays, such as Easter, did not always fall in the proper seasons.  In that year, Pope Gregory XIII authorized, and most Roman Catholic countries adopted, the "Gregorian" or "New Style" Calendar."  As part of the change, ten days were dropped from the month of October, and the formula for determining leap years was revised so that only years divisible by 400 (e.g., 1600, 2000) at the end of a century would be leap years.  January 1 was established as the first day of the new year. Protestant countries, including England and its colonies, not recognizing the authority of the Pope, continued to use the Julian Calendar. 

Double Dating
Between 1582 and 1752, not only were two calendars in use in Europe (and in European colonies), but two different starts of the year were in use in England.  Although the "Legal" year began on March 25, the use of the Gregorian calendar by other European countries led to January 1 becoming commonly celebrated as "New Year's Day" and given as the first day of the year in almanacs.

To avoid misinterpretation, both the "Old Style" and "New Style" year was often used in English and colonial records for dates falling between the new New Year (January 1) and old New Year (March 25), a system known as "double dating." Such dates are usually identified by a slash mark [/] breaking the "Old Style" and "New Style" year, for example, March 19, 1631/2.  Occasionally, writers would express the double date with a hyphen, for example, March 19, 1631-32.  In general, double dating was more common in civil than church and ecclesiastical records.

The Changes of 1752
In accordance with a 1750 act of Parliament, England and its colonies changed calendars in 1752. By that time, the discrepancy between a solar year and the Julian Calendar had grown by an additional day, so that the calendar used in England and its colonies was 11 days out-of-sync with the Gregorian Calendar in use in most other parts of Europe. 

England's calendar change included three major components. The Julian Calendar was replaced by the Gregorian Calendar, changing the formula for calculating leap years.  The beginning of the legal new year was moved from March 25 to January 1.  Finally, 11 days were dropped from the month of September 1752. 

The changeover involved a series of steps:

Which Calendar Is It?
Out of context, it is sometimes hard to determine whether information in colonial records was entered "Old Style" or "New Style." Some examples:

In the Public Records of the Colony of Connecticut, "A Corte at New Towne [Hartford] 27 Decr. 1636" is immediately followed by a court held "21 Febr. 1636," which is followed, in turn, by "A Cort att Hartford, Mrch 28th, 1637". Although it may first appear that the February session was entered out of sequence, the arrangement is actually correct.  Under the "Old Style" calendar and legal new year, 1636 began on March 25.  December 1636 was followed by January 1636 and February 1636, and 1636 continued through March 24.

The "Warwick Patent" is dated the "Nineteenth day of March in the Seventh/ yeare of ye reigne of our Sovergne Lord Charles by ye grace of God/ Kinge of England Scotland Ffrance and/ Ireland defender of ye ffaith &c Anno Dom/ 1631." Although not double dated, the historical context indicates that the date as recorded was "Old Style."  If double dated, it would have been recorded as March 19, 1631/2; if recorded "New Style," it would be March 19, 1632. 

John and Joane Carrington, accused of "familliarity with Sathan the great Enemye of God and mankinde" were indicted by Connecticut's Particular Court on "6 March 1650/1."  In his "diary" or notebook, Matthew Grant records that they were executed "mar. 19.50."  Although Grant did not employ the double date, had he done so it would have been recorded as March 19, 1650/1.

Although current historical scholarship calls for retention of Old Style dates in transcriptions, historians and genealogists need to be aware that some people living at the time converted the date of an event, such as a birthday, from Old Style to New Style.  George Washington, for example, was born on February 11, 1731 under the Julian Calendar, but changed the date to February 22, 1732 to reflect the Gregorian Calendar. 

Links
Cyndi's List:  Calendars and Dates.

The Gregorian Calendar, from the Galileo Project.

"Old Style and New Style Dates," from Wikipedia, the free encyclopedia.

"Old Style and New Style Dates and the Change to the Gregorian Calendar:  A Summary for Genealogists," by Mike Spathaky.

Perpetual Calendar.

Time and Date.com.

"Time to Take Note:  The 1752 Calendar Change"

Bibliography
Garman, Leo H.  "Genealogists and the Gregorian Calendar," NEHGS NEXUS vol. 6, no. 2 (Apr 1989), pp. 61-2.

Greenwood, Val D.  The Researcher's Guide to American Genealogy.  3rd Edition.  Baltimore:  Genealogical Publishing Co., Inc., 2000 [CSL call number History Reference CS 47 .G74 2000].  See "The Calendar," pp. 43-5.

Haydn, Joseph.  Haydn's Dictionary of Dates and Universal Information Relating to All Ages and Nations. New York: G. P. Putnam's Sons, 1904 [CSL call number D 9 .H452].

Herber, Mark D.  Ancestral Trails:  The Complete Guide to British Genealogy and Family History.  Reprint.  Baltimore:  Genealogical Publishing Co., Inc., 1998 [CSL call number CS 414 .H37 1998].

Jacobus, Donald Lines.  "Dates and the Calendar."  The American Genealogist and New Haven Genealogical Magazine vol. IX, pp. 130-135 [CSL call number F 104 .N6 A65].

___________. Genealogy as Pastime and Profession.  Second Edition Revised.  Baltimore:  Genealogical Publishing Co., Inc., 1978 [CSL call number CS 16 .J3 1968].  See Chapter XVIII, "Dates and the Calendar," pp. 109-13, a revision of The American Genealogist article, above.

Prindle, Paul W., "The 1752 Calendar Change." The American Genealogist 40 (October 1964), pp. 246-8; 41 (April 1965), p. 98 [CSL call number F 104 .N6 A64].

Rubicam, Milton.  Pitfalls in Genealogical Research.  Salt Lake City:  Ancestry Pub., 1987 [CSL call number CS 14 .R83 1987].  See Chapter 4, "The Problem of Dates," and Chapter 5, "The 1752 Calendar Change."

Smith, Kenneth Lee.  Genealogical Dates:  A User-Friendly Guide.  Camden, Maine:  Picton Press, 1994 [CSL call number CS 14 .S65 1994

Smith, Mark M.  "Culture, Commerce, and Calendar Reform in America."  William and Mary Quarterly, 3rd Series, vol. 55 (October 1998), pp. 558-84 [CSL call number E 186 .W55]. Explores "how colonists learned of the reform, assesses how they reacted, suggests why they responded to the temporal reconfiguration as they did, and points ... to the potential significance of the reform...."

Wilson, George B.  "Genealogy and the Calendar."  Maryland Magazine of Genealogy 1 (Fall 1978): 13-20 [CSL call number F 180 .M347]

Young, Henry C.  "The Gregorian Calendar and its Effect on Genealogical Research." Niagra Frontier Genealogical Society Magazine, June 1944, pp. 148-51 [CSL call number F 127 .N6 N61].

Prepared by the History & Genealogy Unit, Sept. 2008