I know a case, not a princess, but somewhat of a prince.

First things first, why do I say "somewhat of a prince". King Philip IV of Spain was known as a serious womaniser, and had an unclear number of bastard children, but far over a dozen. One of these children would be very close to his heart: Juan José de Austria. Philip recognised this bastard son as his, and while not legitimised, Juan José was granted the titles of Serenity and Highness. Furthermore, he was created "Prince of the Sea" in 1647, which is a fancier version of "Admiral Major", but which ranks him amongst the princes though out of the line of succession.

This Juan José de Austria always had the King's favour, until he didn't. In 1665, Juan José presented his father a small painting showing the king as old Saturn, Juan José as Jupiter, and infanta Margarita as Juno. The implication was very clear: Juan José wanted to marry his half-sister and eventually become king. Philip IV was livid at that proposal, expelled Juan José from the Court and banished him from Madrid. Juan José never saw his father again, who died that same year.

I can think of one example which is close to what you want. But bear in mind, a princess is a princess and as such valuable goods even being damaged either way, so you never really throw them away. And yes the words I used are deliberately iffy for modern times, but that's how it shakes out for a royal princess.

Cecilia Vasa (1540-1627), one of the lesser known of the Vasas, because well, history is HIStory sometimes. And her father who effectively founded modern Sweden, and her three brothers who all became kings in turn (in a series of plots that gives Game of Thrones a run for it's money. I swear if it only had dragons too it'd be on Netflix...) has tended to overshadow her.

She was born the 4th child of king Gustav, and was educated as well as the period could a royal princess. Also she was a party princess together with her older sister. Constantly causing problems for their increasingly grumpy father. I'm not defending the thinking, but for the king his daughters were problematic and their behaviour a matter of state security, since the royal dynasty was brand new and in the European context jumped up usurpers. The previous union king Kristian II was still alive, though in captivity by his Danish relative and replacement as Danish king Fredrik I. This is pertinent since Kristian was married to the sister of the Holy Roman Emperor Charles V and ostensibly had been trying to regain his Nordic crowns as a restored Catholic ruler. Any loss of prestige for members of the Vasa dynasty reflected on the family and by extension weakened the nation. King Gustav had plenty of enemies and few friends.

Since his family prestige was rather lacking he equipped her with a 100,000 daler dowry (financed by his windfall of confiscated church wealth). She was also considered quite attractive. Both sisters were, quite literally, put on the (matrimonial) market. In 1558 a match was made between her a year older sister and Edzard II count of East Frisia. Not as excellent as one could wish but it had to suffice. A marriage took place in October 1559. The bride and groom were escorted towards their new home by, the bride's brother Erik and sister Cecilia as well as Johan the groom's brother. Apparently it devolved into the 1560s version of booze cruise, with the young royals and nobles partying, well, royally. In December they arrived at the town of Vadstena where another of Cecilia's brothers, Magnus, resided and this is where everyone decided to spend Christmas (the king wanted Cecilia back because a marriage was being planned, but there were also concerns about safety). One night the groom's brother Johan is observed sneaking into Cecilia's bedroom. This goes on for a bit and finally the guards take the matter to her brother Erik. The two brothers, Erik (crown prince and royal duke) and Magnus (also royal duke), decide to surprise the nightly suitor with his pants down. Literally as it turns out. The brother's report to the king states he was found in their sister's rooms only clad in a shirt barely wearing his trousers. This scandal was naturally quietly and discreetly handled.

Naaah, of course not, these are the Vasas we talk about after all. The resulting actions are known as the "Vadstena ruckus". Johan was throw into prison, and later sent to be held by the king. The bride and groom were were placed into house arrest. And Cecilia's father had a frank discussion about her inappropriate behaviour. Or chastised her by tearing her hair out and threatening to kill her if you chose to believe her and her brother's story instead. As I've said before in answers, the Vasas were a choleric lot to a man, and woman. The rest of Europe naturally laughed their behinds off. [citation required]

Johan's relatives and allies plead his case and in 1560 Johan had to swear in front of the king and parliament swear on his and the princess' innocence (read: virginity, conveniently in Swedish the word for both is the same). One solution considered was marrying Cecilia to him. It seems Johan's mother did not particularly care for the match and feared too strong Swedish influence. After taking the oath Johan was able to leave the country (with his pants this time on) and lead the rest of his life quietly, and unmarried. One cannot help but think he was marked by his experience.

The Gustav took the whole affair badly, he blamed his daughter and her brothers for lacking conduct and inability to quiet the affair down. It may well have been one of the issues that pushed him towards his death in September 1560.

Cecilia continued to trouble her brother, the new king Erik XIV, partying with her other sister and their Italian musicians in the middle of the night. Despite a regulation that severely limited the conduct of women and court and in particular those of the royal family. It was in fact punishable by death not to inform the king if inappropriate activities occurred.

She was finally married to the margrave Christopher II of Baden-Rodemachen. She continued a life of less than appropriate living, and racked up an enormous bill while staying in England to work for her brother's matter in the proposing marriage to Queen Elisabeth I. That's just one part of a rather fascinating life, and when she died in 1627, aged 87, the last Vasa to rule Sweden, the future Queen Kristina had been born barley a month prior.

Though leaning towards pop-history is Herman Lindquist's "De vilda Vasarna : en våldsam historia" (2016) is quite good. I do not know if it exist in translations. It has the benefit of covering the entire dynasty in one book so you get all the connections and intriguing in one package. Also he writes very well, occasional factual errors aside. Otherwise Cecilia is often only an accessory to her brother's actions who as ruling kings tend to dominate the stories.

​

She never was "sent away in dishonour" as such. But her actions were severely detrimental to her family. She couldn't care less though and ran her own race regardless. Quite like her brother's really. It shows you can get away with quite a lot though, and society will willingly disbelieve something if needed. Provided you have a dowry great enough at any rate.

I can't think of any incident in Europe where a legitimately-born daughter of a king was banished or disowned. I have a past answer on Throughout history upper-class folk married their children to secure alliances. And while I understand it from an informal or emotional standpoint, I simply don't understand how your son sleeping with my daughter was supposed to make you more loyal on matters of geopolitics? Can someone explain? that may be helpful to you. Princesses would also nearly always be married early in adulthood, if not in adolescence, which severely cuts down on the amount of time they would have to do anything worthy of banishment in their home court.

This may be something where you simply have to bow to your beta reader's point.

Hi there - we're happy to approve your question related to your creative project, and we are happy for people to answer. However, we should warn you that many flairs have become reluctant to answer questions for aspiring novelists and the like, based on past experience: some people working on creative projects have a tendency to try to pump historians for trivia while ignoring the bigger points they were making, while others have a tendency to argue with historians when the historical reality does not line up with what's needed for a particular scene or characterization. Please respect the answers of people who have generously given you their time, even if it's not always what you want to hear.

Additionally, as amazing as our flair panel is, we should also point out that /r/AskHistorians is not a professional historical consultation service. If you're asking a question here because you need vital research for a future commercial product such as a historical novel, you may be better off engaging a historical consultant at a fair hourly rate to answer these questions for you. We don't know what the going rate for consultancy work would be in your locality, but it may be worth looking into that if you have in-depth or highly plot-reliant questions for this project. Some /r/AskHistorians flairs could be receptive to working as a consultant in this way. However, if you wish for a flair here to do this work for you, you will need to organize this with them yourselves.

For more general advice about doing research to inform a creative project, please check out our Monday Methods post on the subject.