Because I am both a writer of historical romance and a teacher, I though we might have a little history lesson today. I’d be willing to bet, though, that this is a lesson you never had in school 🙂
In order to be considered a legitimate child during the Regency, your parents had to be married at the time of your birth. It didn’t matter what their status was at your conception, as long as they made it to the altar—together—before you made an appearance in the world. If you came before the nuptial ceremony, you were illegitimate, forever, even if your parents married later*.
If your mother was married to another man at the time of your birth, you were legitimate, but legally the child of her husband. There are all kinds of subtle (and sometimes not so subtle) jokes and references in Regency and Georgian novels about ladies letting a “cookoo” in the nest—passing off the child of an affair as one belonging to her husband. It’s even a major plot point in Julia Quinn’s It’s In His Kiss: the hero and his “father” both know he’s the product of his mother’s affair, but he’s still the legal heir to his “father’s” title and fortune.
Illegitimate offspring could not inherit entailed property (property that, by law, passed to the next legitimate male heir), or titles. Ever. They could inherit unentailed property (property that could be disposed of in any manner), money, or goods by will—as could anybody else.
A great example of this is Mary Balogh’s A Secret Affair. The hero, Constantine Huxtable, was born two days before his parents’ wedding, thus rendering him ineligible to inherit his father’s earldom (this is actually the basis for the series, as a cousin inherits instead). But wait, you say. Grace Burrowes has a hero who’s illegitimate, and he’s an earl! In The Soldier, Devlin St. Just is the bastard son of a duke, and he does gain an earldom, but not through inheritance. St. Just’s title was granted for service to the Crown during the Napoleonic Wars, and it was the monarch’s prerogative to confer the honor. (Where do you think all those nobles came from in the first place?)
Bastardy was also a bar to society, for the most part. According to Allison Lane, an illegitimate daughter was not accepted or welcome at all socially, while a son could be admitted to the fringes of society with the help and sponsorship of his father. The heroine of Julia Quinn’s An Offer from a Gentleman is a good illustration: she was the bastard daughter of an earl, but never acknowledged as anything other than the earl’s ward, nor did she move in society (except once, but I won’t spoil it for you).
There were exceptions to this rule (there always are, right?), and a big one was William, Duke of Clarence (later William IV) had ten (yes, ten!) illegitimate children with an actress known as Mrs. Jordan. Being the bastard get of a royal duke was clearly a better lot than that of other illegitimate children (and many legitimate ones, too). Since their father was the son and brother of a king (then later a king himself), the FitzClarences, as they were called, did rather well socially. They were given the precedence of the children of a marquess, the eldest son was granted an earldom, and the rest married nobles or the children of nobles.
*For those of you that are familiar with the medieval period, you’re probably jumping up and down right now, yelling “John of Gaunt!” or “Beaufort!” (or maybe you’re yelling something else at me!). Yes, John of Gaunt (son of Edward III) had four children with his mistress Katherine Swynford who were given the surname Beaufort (after one of John’s properties). And yes, they were eventually legitimized by the pope and their cousin Richard II when John scandalized everyone and married Katherine (their children were adults by then). But this was under the medieval Catholic Church, where rules could be bent for the right price, and John was a very powerful man. And this legitimacy was questioned a few generations later when Henry Tudor, great-great-grandson of John through his eldest Beaufort son, claimed the English throne. The Regency was several hundred years after the Reformation, and Britain’s aristocracy was (for the most part) steadfastly Protestant. Different time, different church, different rules.