It could be illegitimate or legitimate. Just depends. Would marrying a commoner before you have a child would that child be legitimate?Assuming that Elizabeth marries, her husband likely becomes co-ruler of England and a very visible force at court, setting his own mark on the age and upsetting the balancing act Elizabeth played between her courtiers. Assuming the marriage happens early in the reign (as is likely if she has a surviving son from it), it also upsets Elizabeth's OTL diplomatic game of dangling the possibility of marriage in front of every crowned head of Europe. The results will be huge.
Assuming that Elizabeth does not marry and has a son outside wedlock, her reputation is immediately and permanently besmirched. Her religious settlement is thrown into disrepute as it's now headed by a known fornicator; Anglicanism probably never recovers. There's a chance England goes Catholic; Presbyterianism or Lutheranism is more likely IMO, but either way, there'll be a whole lot of strife and maybe war. Somewhere in here, Elizabeth probably loses the crown - either to a foreign invasion or (like her cousin Mary Queen of Scots) to internal revolt.
If you want to stick close to OTL, I think the best possibility would be to have Elizabeth marry one of her courtiers but have her husband quickly die leaving her pregnant. Rumors would fly that she had him assassinated, but as long as she doesn't do anything stupid (like Mary Queen of Scots), they'd probably die down leaving her once again available to play her OTL balancing games. She couldn't have the same OTL mystique of the Virgin Queen, but aside from Virginia bearing a different name, that probably wouldn't have many great effects.
I'm afraid that has such a large impact on everything else that we can't answer any questions about the consequences till that's settled.It could be illegitimate or legitimate. Just depends.
Absolutely. Morganatic marriage was completely unknown in England; any marriage would make the resulting child completely legitimate and eligible to inherit. Look at how, several generations before, Richard III's Parliament declared that Edward IV had secretly married his longtime mistress - which meant that his subsequent marriage to Queen Elizabeth Woodville was bigamous, and all his children of that marriage illegitimate.Would marrying a commoner before you have a child would that child be legitimate?
If she marries Thomas Seymour and has a child with him that child can inherit the throne.I'm afraid that has such a large impact on everything else that we can't answer any questions about the consequences till that's settled.
Absolutely. Morganatic marriage was completely unknown in England; any marriage would make the resulting child completely legitimate and eligible to inherit. Look at how, several generations before, Richard III's Parliament declared that Edward IV had secretly married his longtime mistress - which meant that his subsequent marriage to Queen Elizabeth Woodville was bigamous, and all his children of that marriage illegitimate.
Yes, if Elizabeth got the throne in the first place. Elizabeth's relationship with Thomas Seymour took place during Edward VI's reign, and it was Edward's Council who OTL had him executed for treason. If she actually married him, Queen Mary would probably have seen her and Thomas as much more of a threat; Elizabeth might not even have survived, let alone taken the Crown.If she marries Thomas Seymour and has a child with him that child can inherit the throne.
Yes, if Elizabeth got the throne in the first place. Elizabeth's relationship with Thomas Seymour took place during Edward VI's reign, and it was Edward's Council who OTL had him executed for treason. If she actually married him, Queen Mary would probably have seen her and Thomas as much more of a threat; Elizabeth might not even have survived, let alone taken the Crown.