Dating Latin documents

Between 1086 and 1733, a variety of methods were used to date Latin documents. This page will give you a basic introduction to these methods.

We will look at

Remember that this is not a definitive guide.

If you would like to look at dating documents in more detail, ‘A Handbook of Dates: for students of British history’, C R Cheney and M Jones (eds) (Cambridge University Press, revd 2000) is the standard reference work.


Numbers

When numbers are written in full, they are given in these forms.

Latin
English
Latin
English
unus, –a, –um
one primus, –a, –um
first
duodueduo
two secundus
second
trestria
three tertius
third
quattuor
four quartus
fourth
quinque
five quintus
fifth
sex
six sextus
sixth
septem
seven septimus
seventh
octo
eight octavus
eighth
novem
nine nonus
ninth
decem
ten decimus
tenth
undecim
eleven undecimus
eleventh
duodecim
twelve duodecimus
twelfth
tredecim
thirteen tertius decimus
thirteenth
quattuordecim
fourteen quartus decimus
fourteenth
quindecim
fifteen quintus decimus
fifteenth
sedecim
sixteen sextus decimus
sixteenth
septemdecim
seventeen septimus decimus
seventeenth
duodeviginti
eighteen duodevicesimus
eighteenth
undeviginti
nineteen undevicesimus
nineteenth
viginti
twenty vicesimus
twentieth
viginti unus
twenty one vicesimus primus
twenty first
viginti duo
twenty two vicesimus secundus
twenty second
viginti tres
twenty three vicesimus tertius
twenty third
viginti quartus
twenty four vicesimus quartus
twenty fourth
viginti quintus
twenty five vicesimus quintus
twenty fifth
viginti sex
twenty six vicesimus sextus
twenty sixth
viginti septem
twenty seven vicesimus septimus
twenty seventh
viginti octo
twenty eight vicesimus octavus
twenty eighth
viginti novem
twenty nine vicesimus nonus
twenty ninth
triginta
thirty tricesimus
thirtieth
quadraginta
forty quadragesimus
fortieth
quinquaginta
fifty quinquagesimus
fiftieth
sexaginta
sixty sexagesimus
sixtieth
septuaginta
seventy septuagesimus
seventieth
octoginta
eighty octogesimus
eightieth
nonaginta
ninety nonagesimus
ninetieth
centum
one hundred centesimus
one hundreth
centum et unus
one hundred and one centesimus primus
one hundred and first
ducenti, –ae, –a
two hundred ducentesimus
two hundredth
trecenti
three hundred trecentesimus
three hundredth
quadringenti
four hundred quadringentesimus
four hundredth
quingenti
five hundred quingentesimus
five hundredth
sescenti
six hundred sescentesimus
six hundredth
septingenti
seven hundred septingentesimus
seven hundredth
octingenti
eight hundred octingentesimus
eight hundredth
nongenti
nine hundred nongentesimus
nine hundredth
mille
one thousand millesimus
thousanth

Don’t feel that you have to learn them all at once.

If you know any French or Italian, can you see any similarities with the numbers in these languages?

Handy Hints

  1. Keep looking for patterns when you read through the numbers.If you understand how the words are made up, you are more likely to remember them.
  2. Can you see any similarities with English numbers or dates? For example
  •  September is our seventh month (septem means seven)
  •  The decimal system is based on units of ten (decem means ten)

Remember that a few numbers decline:

  • unus, -a, -um
  • duo, due, duo
  • tres, tria
  • ducenti, -ae, -a two hundred declines like novus, -a, -um


Dates

Dates are expressed using ‘first’, ‘second’, ‘third’, rather than ‘one’, ‘two’, ‘three’. These are always in the ablative case. Generally, the ‘us’ ending becomes an ‘o’.

secundo – on the second

centesimo primo die – on the hundred and first day

anno regni regis Johannis filii regis Henrici sexagesimo – in the sixtieth year of the reign of King John son of King Henry

anno domini millesimo ducentesimo quinto decimo – in the year of our Lord one thousand two hundred and fifteen (or, 1215 AD)


Roman numerals

Numbers were expressed in Roman numerals throughout the period covered by this tutorial.

Arabic numerals (1, 2, 3, etc) were also used in England from the 16th century onwards.

In Latin documents, Roman numerals were often written in lower case, rather than in capital letters. If a number ended in an ‘i’, this was often written as a ‘j’.

Classic Roman numerals
Roman numerals in medieval Latin documents
I = 1 i or j = 1
II = 2 ii or ij = 2
IV = 4 iiii or iiij = 4 (not usually iv)
V = 5 V or v = 5
X = 10 X or x = 10
XL = 40 xl = 40 A smaller numeral in front of a larger numeral indicates subtraction.
L = 50 l = 50 Don’t confuse this with ‘i’.
LX = 60 lx = 60 A larger numeral in front of a smaller numeral indicates addition.
C = 100 C = 100
D = 500 D = 500
M = 1000 M = 1000

Months of the year

menses anni
mensis, -is (m.) month

 

Latin word and English meaning
‘month of …’
Januarius, -i (m.) January mensis Januarii
Februarius, -i (m.) February mensis Februarii
Martius, -i (m.) March mensis Martii
Aprilis, Aprilis (m.) April mensis Aprilis
Maius, -i (m.) May mensis Maii
Junius, -i (m.) June mensis Junii
Julius, -i (m.) July mensis Julii
Augustus, -i (m.) August mensis Augusti
September, Septembris (m.) September mensis Septembris
October, Octobris (m.) October mensis Octobris
November, Novembris (m.) November mensis Novembris
December, Decembris (m.) December mensis Decembris

 

decimo Januarii
on the tenth of January
tricesimo primo Decembris
on the thirty first of December
vicesimo octavo die mensis Augusti
on the twenty eighth day of the month of August

Days of the week

dies septimane
septimana, -e (f.) week

 

dies Lune
Monday
dies Martis
Tuesday
dies Mercurii
Wednesday
dies Iovis
Thursday
dies Veneris
Friday
dies Sabbati
Saturday
dies Dominica
Sunday

Feasts

As medieval England was a Catholic country, a large number of religious feast days were celebrated. Many feasts related to a particular saint. These feasts were often used to date events.

For example, a charter might have been granted

in festo sancti Edwardi martiris – on the feast of Saint Edward the Martyr

  • festum, -i (n.) feast
  • martir, martiris (m.) martyr
in vigilia festi – on the eve of the feast
in crastino festi – on the morrow of the feast
  • vigilia, -e (f.) eve
  • crastinum, -i (n.) morrow
Events were also dated
ad festum
on the feast
ante festum
before the feast
apud festum
at the feast
post festum
after the feast

For example

ad festum sancti Johannis baptiste
at the feast of Saint John the Baptist
apud festum beati Thome martiris
at the feast of the Blessed Thomas the Martyr
ante festum sancte Marie virginis
before the feast of Saint Mary the Virgin
  • beatus, -a, -um (m.) blessed
  • Thomas, -e (m.) Thomas
  • virgo, virginis (f.) virgin

A list of the main feasts, with the calendar dates that they correspond to, is given in ‘A Handbook of Dates: for students of British history’, C R Cheney and M Jones (eds), (Cambridge University Press, revd 2000).

Octave

An octave is a period of eight days inclusive.

octaba, -e (f.) octave
octava, -e (f.) octave

You will often see this term used in dates.

For example

in octava festi sancti Michaelis – on the octave of the feast of Saint Michael

  • Michael, Michaelis (m.) Michael
The feast of Saint Michael is on 29 September. Therefore, the octave of the feast is a period of eight days later (inclusive): 6 October.

The table below shows you how to calculate the octave of Saint Michael. You can use the same principle to calculate the octave of any feast.

Feast
Calendar date
Day number
Saint Michael 29 September 1
30 September 2
1 October 3
2 October 4
3 October 5
4 October 6
5 October 7
octave of the feast of Saint Michael 6 October 8