The Book of Baglan is a collection of old Welsh manuscript

Manuscript

A manuscript or handwrite is written information that has been manually created by someone or some people, such as a hand-written letter, as opposed to being printed or reproduced some other way...

s, containing much genealogical data, compiled by John Williams from several sources between 1600 and 1607. It was transcribed from the original manuscript preserved in the public library

Public library

A public library is a library that is accessible by the public and is generally funded from public sources and operated by civil servants. There are five fundamental characteristics shared by public libraries...

 at Cardiff

Cardiff

Cardiff is the capital, largest city and most populous county of Wales and the 10th largest city in the United Kingdom. The city is Wales' chief commercial centre, the base for most national cultural and sporting institutions, the Welsh national media, and the seat of the National Assembly for...

, and edited by Joseph Bradney

Joseph Bradney

Colonel Sir Joseph Alfred Bradney, FSA, BA, JP, DL was a British soldier, historian and archaeologist, best known for his multivolume A History of Monmouthshire.-Life:...

 with explanatory notes for reprinting in 1910. It is also available at the National Library of Wales

National Library of Wales

The National Library of Wales , Aberystwyth, is the national legal deposit library of Wales; one of the Welsh Government sponsored bodies.Welsh is its main medium of communication...

 on microfilm.

It is considered a valuable reference for Welsh genealogy, although it is not considered wholly accurate.Legend of Lewis: Bibliography Retrieved on 2008-09-04. The book contains numerous South Welsh

South Wales

South Wales is an area of Wales bordered by England and the Bristol Channel to the east and south, and Mid Wales and West Wales to the north and west. The most densely populated region in the south-west of the United Kingdom, it is home to around 2.1 million people and includes the capital city of...

 pedigrees of minor gentry families, including local lords, the kings of Gwent, the Earls of Pembroke, and the bard Rhys Goch, and contains descriptions of the heraldry

Heraldry

Heraldry is the profession, study, or art of creating, granting, and blazoning arms and ruling on questions of rank or protocol, as exercised by an officer of arms. Heraldry comes from Anglo-Norman herald, from the Germanic compound harja-waldaz, "army commander"...

of various lines.