ESPN has the most amazing detailed history on The Curse of the Bambino that not only explains how the urban legend started (it's actually a much newer phenomenon than you think; amazing that it started in my lifetime), but also the unsavory reality behind it.
It's a history of Boston parochialism; anti-semitism; Henry Ford; early 20th centruy American attitudes; lies and slander; racism; and the fact you can't liable the dead. How even with all our mass media and ability to record "the truth," history still gets twisted in some pretty amazing ways.
Here's a great paragraph from near the end of the article:
At best proponents of the "Curse" are ignorant of its history. They have done the bidding of others as unknowing pawns in a legacy of hate that dates back centuries, bit players in a larger, older drama far more significant than any ever contemplated by Harry Frazee. Stripped of its source, the hate and misinformation spewed by Ford and later revived by Fred Lieb that survives today in latent form in the "Curse" says nothing at all of value about Harry Frazee, or why the Red Sox have ever won or lost a single game. It does, however, say a great deal about the insidious and sinister nature of hate -- the influence of which lasts generations -- and the danger entailed in believing in anything without ever examining the basis of those beliefs. In today's world people die every day due to the prejudice born in misconceptions. If any "Curse" deserves to broken, that one does.
A comment via Metafilter on this article: "So The Curse that doesn't exist was made up to cover up the antisemitism displayed against a man who wasn't Jewish. Am I reading this right?"
Yes. It appears you are.
And just because I love a good urban legend (heart-breaking history behind it or not), Dave Barry is kind enough to write about one of the many attempts to break the Curse of the Bambino: The Restoration of Babe Ruth's piano. Since I'm familiar with Sudbury (MA), I have to admit I had a hard time not laughing while reading the Barry column.
And as a true-blue Bostonian, I only have this to say: "One more game! One more game! One more game!"