Vlad the Impaler
Vlad was living in exile because he was afraid of the boyars of Wallachia. Vlad escaped to Hungary but he was put in prison there. The exact time of Vlad's captivity is not known for sure. Apparently his imprisonment was not too dangerous. He was able to gradually win his way back into the favor of King Matthias. He was able to meet and marry a member of the royal family (the cousin of King Matthias). However, some do not believe that it was likely to happen that a prisoner was permitted to marry into the royal family.