There are several references to historical eclipses in the British Isles in ancient manuscripts, including the Anglo-Saxon Chronicles and several Irish annals. Many of these references are fairly widely known.

Less well-known, if at all, are the brief accounts of eclipses, both solar and lunar, in the Brut y Tywysogion, the Chronicle of the Princes, which chronicles events in the kingdoms of Wales over several centuries up to the early fourteenth century. These eclipse references from the Brut y Tywysogion are reproduced here. These manuscripts extend the historical record to later centuries than the Annales Cambriae (Annals of Wales).

The source of these quotes is the edited version of the Chronicles by Thomas Jones, Brut y Tywysogion, or, the Chronicle of the Princes: Red Book of Hergest version, University of Wales Press, Cardiff, 1955. The original Welsh text is given first, followed by the translation into English provided by Thomas Jones. The dates quoted in square brackets are those given by Thomas Jones.

[-807] Ac yna y bu varw Arthen, vrenhin Keredigyawn. Ac y bu diffyc ar yr heul.
[-807. And then died Arthen, king of Ceredigion. And there was an eclipse of the Sun.]
This appears to be an account of the partial eclipse of 11th February, 807. The eclipse was annular in Scotland and the northern half of Ireland.

[810-810] Deg mlyned ac wythcant oed oet Crist pan duawd y lleuat dyw Nadolyc. Ac y llosget Mynyw. Ac y bu varwolaeth yr anifeilet ar hyt ynys Brydein.
[810-810. Eight hundred and ten was the year of Christ when the Moon darkened on Christmas day. And Menevia was burnt. And there was a mortality of animals throughout the island of Britain.]
A total lunar eclipse occurred on the evening of the 14th December, 810 (on the Julian calendar).

[830-831] Deg mlyned ar hugein ac wythgant oed oet Crist pan vu diffyc ar y lleuat yr wythuet dyd o vis Racuyr. Ac y bu varw Satur[n]biu, esgob Mynyw.
[830-831. Eight hundred and thirty was the year of Christ when there was an eclipse of the Moon on the eighth day from the month of December. And Sadyrnfyw, bishop of Meneva, died.]
It is difficult to identify this report with any predicted lunar eclipse. There was a partial lunar eclipse on 4th November, 830 (on the Julian calendar).

[1137-1138] Ac yna y bu diffic ar yr heul y deudecuetyd o Galan Ebrill.
[1137-1138. And there was an eclipse of the Sun on the twelfth day from the Calends of April.]
This appears to be a reference to the total solar eclipse of 20th March, 1140, although the date given by Thomas Jones is two years early. The Anglo-Saxon Chronicles also report the eclipse and give the date as the thirteenth day from the Calends of April, 1140. The eclipse of 20th March, 1140, was total across all of Wales except Ynys Môn.

[1184-1185] Yn y ulwyddyn honno dyw Calan Mei y sumudawd yr heul y lliw; ac y dywat rei uot anei diffyc.
[1184-1185. In that year on the day of the Calends of May the Sun changed its colour; and some said that it was under an eclipse.]
The solar eclipse of 1st May, 1185, was total across the Scottish Highlands, the Western Isles and Orkney.

[1191-1191] Ac y bu diffyc ar yr heul.
[1191-1191. And there was an eclipse of the Sun.]
An annular eclipse took place across the north of Ireland, the extreme northern coastal fringe of Wales and the North of England on 23rd June, 1191.

We therefore find that there are four references to solar eclipses in the Bryt y Tywysogion and one to a lunar eclipse. Of these four solar eclipses, one was total in Wales and the other three were partial over Wales (although in one of these the annular phase did clip the northern coast of Wales).

There is one more event which may refer to a lunar eclipse. The Red Book of Hergest version of the Brut begins in the year 680. For the year 689, it reports a "rain of blood" and that milk and butter turned "into blood". In the context of this, for the year 691 it reports,

[-691] A'r lleuat a ymchoelawd yn waedawl liw.
[-691. And the moon turned to the colour of blood.]
This could be an account of the total lunar eclipse of 17th May, 691. However, the references to blood colours in other contexts in the preceeding entries complicates this interpretation.
Interestingly, between 500 A.D. and 1300 A.D., the solar eclipses of 3rd September, 639, 29th October, 878, and 24th January, 1023, were total in Wales but were not referred to in the Chronicle. In addition to these, there were several partial eclipses of large magnitude which do not appear in the manuscripts.

Details of solar eclipses were taken from the book UK Solar Eclipses from Year 1 by Sheridan Williams, published by the Clock Tower Press. Details of lunar eclipses came from the Five Millennium Catalog of Lunar Eclipses, -1999 to +3000 by Fred Espenak of NASA's Goddard Space Flight Center.

Incidentally, the Bryt y Tywysogion refers to another astronomical event: the comet of 1106.

by Bryn Jones