The document discusses the challenges of encoding historical dates accurately within projects, particularly in relation to the inconsistencies between the Julian and Gregorian calendars. It outlines the goals of achieving interoperability among various historical research projects and proposes solutions for effectively managing date discrepancies. The authors conclude that it is both practical and worthwhile to encode historical dates correctly, emphasizing the importance of clarity and accuracy in historical scholarship.

1. DH 2013, Lincoln, Nebraska
Encoding historical dates correctly:
Is it practical, and is it worth
it?
Janelle Jenstad, Martin Holmes, Nathan Phillips,
Sarah Milligan, and Cameron Butt
University of Victoria
mapoflondon.uvic.ca
@janellejenstad
@MoEMLondon

2. The Glorious Revolution

3. The Glorious Revolution

4. The Glorious Revolution

5. The Glorious Revolution

6. A Journey through Italy and
France (R.A. Poole)

7. A Journey through Italy and
France (R.A. Poole)

8. A Journey through Italy and
France (R.A. Poole)

9. A Journey through Italy and
France (R.A. Poole)

10. A Journey through Italy and
France (R.A. Poole)

11. Calendrical chaos between countries
1. Julian versus Gregorian calendar
● 1582: Pope Gregory's new calendar
● 1752: English adoption of Gregorian calendar
2. Start of New Year
● March 25, from 1155 to 1752 in England

12. Problem? What problem?
We asked a number of colleagues on cognate
projects for advice:
● It's only a few days. How important could it be?
● Proper historians know perfectly well what a particular
date means.
● It's definitely a mess, but there's no workable solution.
● I don't want to think about it.

13. This problem: Interoperability
● You: a historian of 17thc Holland.
● Me: a researcher on 17thc English literary
texts.
● Your eventography and my eventography get
all interoperable with each other.
● Result: a very silly timeline.

14. Our project
The Map of Early Modern London
(mapoflondon.uvic.ca)
● Covers 1550-1650
● 4105 dates or date ranges encoded so far
● Principal challenge: Stow's Survey of London
● For any date before 1752, we have to STOP before
we tag; W3C standard is meaningless
<date when="1603-03-24">

15. Our goals in encoding dates
1. We want to know WHEN an event occurred
relative to other events (astronomical years).
2. We want dates to be computable and
translatable to other calendars.
3. We want to interleave our dated events with
events in other projects without appearing to
"time travel" like William of Orange.

16. Solutions?
Fact: TEI uses ISO and W3C standards,
which presuppose Gregorian dates.
A solution: convert all dates to Gregorian
before encoding
● Elizabeth died on April 3, 1603 (proleptic Gregorian).
Fact: TEI uses ISO and W3C standards,
which presuppose Gregorian dates.
A solution: convert all dates to Gregorian
before encoding
● Elizabeth died on April 3, 1603 (proleptic Gregorian).

17. Problems with that solution
Produces historical disorientation,
because we "know" that Queen Elizabeth
died on March 24, 1602/3 …
… and it's laborious.

18. Our solution
● Use full capability of TEI
● Class of attributes: att.datable.custom
● "provides attributes for normalization of
elements that contain datable events to a
custom dating system"

19. Attributes we need
1.@when-custom fixed date→
• @notBefore-custom
• @notAfter-custom ...
2.@datingMethod indicates the calendar→
assumed by the value of the attribute(s) above
3.@calendar indicates the calendar used in the→
text being marked up

20. Various reckoning systems
Primary texts reckon time by:
regnal years ("the third of King John")
papal years
mayoral years
Anno Mundi (years since Creation)
legal terms
Saint's days
Custom MoEML @calendar values include:
calendar="mol:anno_mundi"

21. What the encoder sees

22. What the site will give you

23. What the reader sees

24. So ...
… is it practical, and worthwhile to encode
historical dates correctly?
YES!
It is practical,
and it is worth it!

25. Credits and thanks
Social Sciences and Humanities Research Council
Humanities Computing and Media Centre, UVic
MoEML Team, especially Nathan Phillips, Sarah Milligan,
and Cameron Butt
Correspondence: jenstad@uvic.ca