Brut y Brenhinedd was the name under which the Welsh translations of Geoffrey of Monmouth's Historium Regnum Britanniae was known. Written in 1136 this purported to be a history of the Kings of Britain until the time of Cadwaladr Fendigaid "the last king there was over the Britons". As Brut y Brenhinedd was the Chronicle of the Kings, or the history of the Kings of Britain; Brut y Tywysogion was therefore intended as its sequel, the Chronicle of the Princes or the history of the Kings of Wales.
The Brut originates in a Latin chronicle compiled sometime in the late thirteenth century. Unfortunately this original Latin chronicle has not survived; it was however translated into Welsh and therefore exists in three separate versions, each of which is considered an independent translation of the original work (and are therefore sometimes collectively known as the 'Brutiau'.)
These three versions are;
The least dependable of the three versions is the Brenhinoedd y Saeson, the fullest and most complete is the Peniarth MS 20 version, but the least inaccurate is the Red Book of Hergest. But all three versions contain what are considered obvious mistranslations from the original Latin and occasionally disagree with one another. Much effort is therefore expended in comparing the text of each version in order to deduce exactly what the original text was trying to say.
From the comparison of the three versions it is summarised that the original chronicle was an account of events from the death of Cadwaladr Fendigaid in the year 682 to the death of Llywellyn ap Gruffudd, the last native ruler of Wales in 1282. (Although the Peniarth version includes a continuation relating to events in the years 1283 to 1332 which were added to the main text by at least two different hands; and Brenhinoedd y Saeson, at least in the Black Book of Basingwerk continues until 1461.)
As far as the sources used by the original compiler of the Latin chronicle, as regards the years 682 to 954 the entries are clearly derived from the Harleian MS 3859 version of the Annales Cambriae. For the remainder of the period it is believed that the source was primarily a set of contemporary annals kept at St Davids and at the Cistercian foundations of Llanbadarn Fawr and Ystrad Fflur (or Strata Florida) of which some fragmentary evidence survives in terms of;
- the annals recorded on the flyleaves of the Breviate of Domesday Book in the Public Record Office
- the Exeter Cathedral MS 3514 known as the Cronica de Wallia which includes an incomplete set of annals for the years 1190-1266
- the annals recorded in BM Cotton MS Domitian AI which is itself a continuation of the aforementioned Harleian MS 3859 to the year 1288
For many centuries it was presumed that the Brut was the work of Caradog of Llancarfan; a contemporary of Geoffrey of Monmouth; if only because Geoffrey at the conclusion of his work, stated that he left to Caradog the job of recording the history of "the kings of the Britons who since the time of Cadwaladr have succeeded in Wales."
It was not until the beginning of the twentieth century that the historian John Edward Lloyd first came to the conclusion that the versions of the Brut were in fact translations of the same Latin work (and absolutely nothing to do with Caradog of Llancarfan), and only in 1928, when John Edward Lloyd gave his British Academy lecture on the subject of the Welsh Chronicles, was it fully understood that there were indeed three entirely separate translations.
The identity of the individual who first compiled the original Latin chronicle is unknown, and nothing is known of the circumstances in which it was created other than it was clearly a product of Welsh medieval monastic scholarship and intended as a continuation of the Historium Regnum Britanniae.
The inspiration may have derived from Geoffrey of Monmouth's work, but unlike Geoffrey's rather fanciful concoction the versions of the Brut y Tywysogion are a largely factual annalistic record of Welsh History. They remain the prime source of our knowledge of events in Wales during the period between 944 and 1282 and are described by the aforementioned John Edward Lloyd "as the greatest monument of Welsh historiography in the Middle Ages".
For a fuller discussion of the various manuscripts that comprise the 'Brutiau' and of their history and provenance see the introductions to the translations of the three versions by Thomas Jones and published by the Univerity of Wales Press in its 'History and Law' series.
The word Brut is derived from Brutus who of course came from Troy to Britain, conquered the giants and founded London and from whom all the Kings of Wales were descended, (Very much like legend of Aeneas who also came from Troy and was responsible for the founding of the city of Rome.) and is used here in the sense of a history or chronicle