Skip to main content


Brycheiniog was a medieval Welsh kingdom whose dynasty is traditionally said to have begun with Brychan, the son of a 5th-cent. Irish chieftain and the daughter of the king of Garthmadrun in the Vale of Usk. His line ended c.940, when Brycheiniog fell under Deheubarth's influence. It was conquered by Bernard of Neufmarché (1093), whose new marcher lordship was known as Brecon (a corruption of Brychan). Brecknock is the English version of Brycheiniog. The lordship was the basis (with Builth lordship) of the new county of Brecon in 1536; it lasted until 1974 when it was incorporated in Co. Powys. Brycheiniog is used as the Welsh version of Breconshire.

Ralph Alan Griffiths

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Brycheiniog." The Oxford Companion to British History. . 20 Jul. 2019 <>.

"Brycheiniog." The Oxford Companion to British History. . (July 20, 2019).

"Brycheiniog." The Oxford Companion to British History. . Retrieved July 20, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.