TITLE: What are some famous rejections of correct mathematics?
QUESTION [133 upvotes]: Dick Lipton has a blog post that motivated this question. He recalled the Stark-Heegner

Theorem: There are only a finite
number of imaginary quadratic fields
that have unique factorization. They
are $\sqrt{d}$ for $d \in \{-1,-2,-3,-7,-11,-19,-43,-67,-163 \}$.

From Wikipedia (link in the theorem statement above):

It was essentially proven by Kurt Heegner in 1952, but Heegner's proof had some minor gaps and the theorem was not accepted until Harold Stark gave a complete proof in 1967, which Stark showed was actually equivalent to Heegner's. Heegner "died before anyone really understood what he had done".

I am also reminded of Grassmann's inability to get his work recognized.
What are some other examples of important correct work being rejected by the community?
NB. There was a complementary question here before.

REPLY [20 votes]: René Schoof once told me that when he submitted his PhD Thesis, the chapter containing his algorithm to compute the number of points of elliptic curves over finite fields did not appeal at all to the referee, who wondered whether such questions had some interest at all... History decided otherwise!