Board Thread:General Discussion/@comment-7526254-20150520160921/@comment-25926288-20150812014311

The writers say so. Prior to Poor Unfortunate Soul, Eddy (I think) says that Hook and Ursula's story takes place in 1819

http://www.ew.com/article/2015/03/20/spoiler-room-scoop-greys-glee-orphan-black-and-more

That is 164 years piror to the curse. Hook and Rumple clearly have been around for some unknown stretch of time before that. Add 30 years to that and that event happened like 200 years ago. Rumple was Dark  One for a some unknown amount of years before that and he was like 50 before becoming Dark One, so he is definitely older than 250. So saying roughly 300 isn't farfetched whatsoever.

Couple houdred is vague, less than 5 hundred. Hook says he's like 200, but that's probably him flirting or whatever, since Emma also calls him 300 years old.

Hopefully, that makes sense! This time the writers aren't incompetent with numbers!