It did happen. In the true story, Pocahontas saved John Smith. It just didn't happen the way it did in the movie and there was nothing romantic between them.
Other famous Johns: John Calvin, John Goodman, John Wilkes Booth, John D. Rockefeller, John Candy, John Hurt, John Wayne Gacy, John Fogerty, John Cena, John Locke, John Deere, John Stamos, John Williams.
http://en.wikipedia.org/wiki/John_Rolfe
The "Animal House" hint is a bit ambiguous, as the movie was also directed by a famous John (Landis).
https://www.reddit.com/r/todayilearned/comments/1af1io/til_that_john_lennon_beat_his_wife_and/