Which bastards are acceptable as qualifying ancestors for joining the Descendants? There are a few different ways for this question to be considered.

Why just kings?  No queens? The name of the society—”Descendants of Illegitimate Sons and Daughters of the Kings of Britain”—seems gendered. Why only kings?  The simple fact is that among scholarly catalogues of known illegitimate children of sovereigns, there are no scholarly accepted bastard children of female sovereigns, nor any known bastards of queen consorts, at least borne while they held the position of queen.  But membership extends to descendants not only of sovereigns’ bastard children, but of the bastard children of children or grandchildren of a sovereign. Most known royal parents of such bastard grandchildren or great-grandchildren are men, but not all. To make it clear that descent paths through royal women are accepted, the constitutional language of the Society was revised slightly in 2006 to encompass descent from any “illegitimate child, grandchild, or great-grandchild of a king of England, Scotland, Great Britain, or the United Kingdom.” The best-known royal woman to bear an illegitimate child is Constance, Countess of Gloucester (c.1374–1416), a granddaughter of King Edward III, who bore a daughter, Eleanor Holand, from a liaison with Edmund Holand, Earl of Kent. Eleanor has traceable descents to a few American immigrants; applicants through Constance and Eleanor are most welcome.

Why not Wales? Why not Gytha of Wessex? Our society’s earliest articulation of qualifying sovereigns of “Britain” included those reigning in England and Scotland, but conceptually there is no bar to enrolling descendants of more modern sovereigns, after 1707, when “Great Britain” came into use, or even after 1801, when “United Kingdom” came into use. So these two kingdoms have been added to our statement of criteria. Going back in time in the Middle Ages, however, raises a different question. The adoption of definitions of legitimacy and illegitimacy, related to the concept of sacramental Christian marriage in Western Europe, is generally recognized as a twelfth-century phenomenon, so the Descendants do not consider lines from children of sovereigns before the twelfth century. This includes the well-known line of descent from King Harold II Godwinson (defeated at Hastings, 1066), through Gytha, daughter of his union with Eadgifu “Swann nhesce”, disparaged by Norman churchmen as “contracted in the Danish fashion” (more danico) and illegitimate or bigamous—but not, by other contemporaries, considered to contravene social norms. (Lines of descent from Gytha were previously accepted for membership in the Descendants but are no longer, for this reason.) Similarly, what we might see as illegitimate children within the families of the last sovereign princes of Wales, even later than the twelfth century, are also not accepted because in Wales, the concept of illegitimacy remained alien for generations because (as readers of Ellis Peters’s Brother Cadfael mysteries should know) it contravened centuries of established Welsh social and legal custom.

Legitimatio per matrimonium subsequens. One famous category of royal bastards are the children of John of Gaunt, Duke of Lancaster, by his longtime mistress, Katherine Roet, who bore him four children surnamed Beaufort, all legitimated by Papal dispensation after his marriage to her years later. Lee Sheppard, in his 1974 article on the Descendants (linked elsewhere on this website), noted that the Beaufort children, and all such subsequently-legitimated royal bastards, are not to be used for membership lines by the Descendants.

Frequently-encountered bastards. So who are the most commonly referenced royal bastards for membership lines among the Descendants?  Lee Sheppard mentioned some of the most frequently claimed bastards in his article. Fifty years later, these same twelfth- and thirteenth-century royal bastards still account for most registered lines to the Descendants:

• Robert of Caen, Earl of Gloucester, son of King Henry I of England
• William Longespée, Earl of Salisbury, son of King Henry II of England
• Richard [of Dover], son of King John of England
• Richard de Cornwall, son of Richard, Earl of Cornwall, son of King John of England
• Isabel, daughter of William I “the Lion”, King of Scots, and wife of Robert de Ros of Helmsley (a Magna Carta surety)

Later lines in use by Descendants include fifteenth-century and even seventeenth-century bastards. For further reading about the history of the concept of royal bastards, and for compendia of royal bastards, refer to A Royal Bastards Bibliography on this site.