Women's Property and Marriage
One of the common misconceptions about the Regency era is that women lost all their property when they married but no, they didn't always. Things could be kept in their name despite their losing their legal identity and it actually shows up in several novels from the time, as we see here in the fragment of Sanditon by Jane Austen:
>Lady Denham had been a rich Miss Brereton, born to wealth but not to education. Her first husband had been a Mr. Hollis, a man of considerable property in the country, of which a large share of the parish of Sanditon, with manor and mansion house, made a part. He had been an elderly man when she married him, her own age about thirty. Her motives for such a match could be little understood at the distance of forty years, but she had so well nursed and pleased Mr. Hollis that at his death he left her everything—all his estates, and all at her disposal. After a widowhood of some years, she had been induced to marry again. The late Sir Harry Denham, of Denham Park in the neighbourhood of Sanditon, had succeeded in removing her and her large income to his own domains, but he could not succeed in the views of permanently enriching his family which were attributed to him. She had been too wary to put anything out of her own power and when, on Sir Harry's decease, she returned again to her own house at Sanditon, she was said to have made this boast to a friend: "that though she had got nothing but her title from the family, still she had given nothing for it."
How was this possible since women were not a separate person before the law? It was done through trusts:
family lawyers set up what was called "separate property" and/or a "separate estate" for brides, especially if they were heiresses. This was basically a trust overseen by the Chancery Court which gave the women access to all her property and money upon application to a trustee, but kept it out of control so her husband couldn't "kiss or kick it" out of her, nor his creditors take it to pay his bills.
What Jane Austen Ate and Charles Dickens Knew, Daniel Pool
Now was this common? This I don't know, and I doubt it was super common, but if a woman was extraordinarily wealthy, she could get lawyers just as good as her husband's and make it happen. I think it's telling that Lady Denham is older and very well off, she has the money and the knowledge to keep her wealth protected.
This is also probably exactly what Darcy set up for Lydia, with the £1000 settled on her. That is her protected dowry and jointure, kept in trust so Wickham can't burn through it:
You know pretty well, I suppose, what has been done for the young people. His debts are to be paid, amounting, I believe, to considerably more than a thousand pounds, another thousand in addition to her own settled upon her, and his commission purchased. - Pride & Prejudice
I like to think that Sophia Grey from Sense & Sensibility kept a lot of her fortune in separate property and she uses that to keep Willoughby in line. The way the narrator talks about his wife "not always being out of humour" makes me think she was holding something over him, and we know she was filthy rich. I also feel like Mrs. Ferrars might have had a lot of separate property, since she is the one controlling all the wealth after her husband dies, instead of it going to her eldest son.
Anyway, this is why marriage articles and not eloping was so important!
(Edit for quote fixing)