Blennerhassett Family Tree
Genealogy one-name study      by Bill Jehan
   Introduction      The earliest dated Blennerhassett coat-of-arms
Blennerhassett arms, Cumberland, in Thomas Jenyn's Book, c1410
arms of John de Blenerhasset, Cumberland
earliest surviving illustration of the Blennerhassett coat-of-arms
in Thomas Jenyn's Book of Arms (Thomas Jenyn's Roll)
Queen Margaret's version
Queen Margaret, consort of King Henry VI of England
The earliest known representation of Blennerhassett coat-of-arms known appears for John de Blenerhasset in a bound folio Ordinary of Arms known as Thomas Jenyn's Book (sometimes "Thomas Jenyn's Roll"), Queen Margaret's version.

The book is believed to have been compiled c1398 (21/22 Richard II) although one source appear to suggest the arms illustrated in Thomas Jenyn's are earlier, perhaps temp. Edward III (1327-1377), and another source suggests later c1410 (Henry IV).
It is difficult to be precise about the date of a particular shield without knowing the dates of birth and death of the individuals named on the shield, e.g. John de Blenerhasset.
The book later belonging to Queen Margaret, a.k.a. Margaret of Anjou (b.1430 d.1482), second daughter of René I of Naples and Isabella, Duchess of Lorraine.  As the wife of the Plantagenet King Henry VI of England she was Queen consort of England 1445 -1461 & 1470-1471 and a leader of the Lancastrian side during the Wars of the Roses. She was also Queen consort of France 1445-1453.
The book, formerly held at the British Museum Library, is now at its successor, the British Library, in the Department of Manuscripts as ref: Add. Ms. 40851, f.68. The individual shield is numbered 1498, on page 126. The book has been microfilmed.
[BL Add.Ms.40851 f.68 p.126] [BL microfilm M2105 (monochrome)] [Boos TJ] [FCA] [HUDDLESTON p.28] [TG vol.5 p.98] 
The volume belongs to a small group of medieval ordinaries of English arms that includes Cooke's Ordinary c1340, Cotgrave's Ordinary c1340, and William Jenyn's Ordinary (also known as William Jenyn's Roll) c1380.  William Jenyn's Ordinary was collated c1380, temp. Edward IV, and later made into a folio book of arms by William Jenyns, Lancaster Herald 1516-1527.  The original is preserved at the College of Arms, London [Ms. Jenyns' Ordinary], another version at The Society of Antiquaries, London [Ms.664/9].

The arms are represented as: Gules three dolphins embowed Argent with a description in French: "1498 John de Blenerhasset port de Gules a trois dolphins Argent", 1498 being the number of the shield within the book.
This is a rare instance of the early form of Blennerhassett arms, displayed without a chevron. The chevron has appeared on all subsequent representations of these arms.
The first name of each of the bearers of the arms illustrated was intended to be written using a distinctive colour for the initial letter, but this initial letter was not added, so in this example the letters J for John and R for Robert are missing.  It has been suggested they may have been added in a distinct colour that over time faded, but that is unlikely, the pages have never been exposed to light for long.
This is a rare, perhaps unique, surviving instance of Blennerhassett arms displayed without a chevron, as it would probably have looked when the arms were first granted.  The chevron that has appeared on all Blennerhassett arms since that time was no doubt added to differentiate the family of a younger son from the family of the eldest son, at a date before the standardised use of marks of cadency. The line of the elder son then becoming extinct, the arms with a chevron became the norm. There can be little doubt that the arms shown here, without a chevron, are the original form. 
photo: copyright © The British Library Board 2010
photo: copyright © The British Library Board 2010

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