Princess Peach's named *used* to be Princess Toadstool in earlier games. Citing this from Wikipedia http://en.wikipedia.org/wiki/Princess_Peach (Gee, I love that site sometimes... heheh.) "In Japan, the Princess's name has always been Peach, but when Super Mario Bros. was released in America, Nintendo of America decided to rename her Princess Toadstool,[4] probably because she was the princess of the Mushroom Kingdom, and "Toadstool" is a type of mushroom. She kept this name throughout the 8-bit and 16-bit video game eras. Often, however, in-game text only referred to her as "Princess" or "The Princess," most likely a result of space constraints. In Super Mario RPG: Legend of the Seven Stars she was referred to as just "Toadstool." The English translation of Yoshi's Safari was the first usage of the name "Peach" outside of Japan; however, the name did not catch on at that time. When Super Mario 64 was released in North America, she signed a letter to Mario "Princess Toadstool" and then handwrote "Peach," which led many fans to believe that her full name is "Princess Peach Toadstool," with her first name Peach, and last name Toadstool. However, others think that "Peach" is her nickname, and she is of the royal house of the Mushroom Kingdom. It is also worth noting that she mentions a cake in the letter, and this could have led people to believe that she was mentioning the cake's flavor, considering very few people knew that her nickname was "Peach". In sequels and spinoffs, however, she has come to be known only as Princess Peach"