Theorems' names that don't credit the right people The point of this question is to compile a list of theorems that don't give credit to right people in the sense that the name(s) of the mathematician(s) who first proved the theorem doesn't (do not) appear in the theorem name. 
For instance the Cantor Schröder Bernstein theorem was first proved by Dedekind.
I'd also like to include situations in which someone conjectured something, didn't prove it, then someone else conjectured the same thing later, also without proving it, and was credited with having first conjectured it.
Similar unfair things which I didn't remember to include might also be considered.
Some kind of reference is appreciated.
 A: Burnside's lemma was first proved by Frobenius. Vandermonde's identity was known in China long before. Pólya's enumeration theorem is due to Redfield. And $3/4$ of calculus was proved by Euler, but credited to all sorts of other people!
The list goes on ad nauseam.
A: Stokes' Theorem was basically formulated by everyone else but Stokes.
A: Fibonacci's contributions to the study of the Fibonacci sequence are essentially zero. One of the numerous arithmetic exercises in his 1202 book Liber Abaci is to calculate the decimal expansions of the first twelve Fibonacci numbers; this is the source of the name, and his sole connection with the problem.
A: How about the famous cryptosystem RSA? It was named after Ron Rivest, Adi Shamir and Leonard Adleman who invented it in 1977, but it was already invented years earlier (1973) by Clifford Cocks. Unfortunately for him his invention was classified, and only 20 years later it turned out that he was actually the one who discovered the algorithm first...
A: Wikipedia has an article on everything: List of misnamed theorems.
A: Zorn's lemma was formulated and proved in various forms prior to Zorn, going back to the Hausdorff maximal principle.  The version currently known as "Zorn's Lemma" was formulated and proved by Kuratowski in 1922.  Zorn's contribution, in 1935, was an equivalent but different maximal principle.
(See Paul J. Campbell, "The Origin of ‘Zorn's Lemma’", Historia Mathematica 5 (1978), pp. 77–89.)
A: Obviously this list is incomplete without Stigler's law of eponymy, stipulating that no scientific discovery is due to the person it is named for, and which, according to Stigler, is due to Robert K. Merton.
http://en.wikipedia.org/wiki/Stigler%27s_law_of_eponymy
[I know this is not a theorem. We have "eponysterical". Has anyone coined "ironymous" or "erronymous"?]
A: My contribution:
$\bullet$ The  Cantor Schröder Bernstein theorem was first proved by Dedekind.
$\bullet$ The Cauchy-Schwarz inequality should perhaps also be credited to Viktor Bunyakovsky and Cauchy.
A: Not quite an answer but maybe relevant:
Arnold's Principle: If a notion bears a personal name, then this name is not the name of the discoverer.
Berry Principle: Arnold's Principle is applicable to itself. 
[source]

By the way this MO thread on Arnold's principle contains a lot of actual answers to OP question.
A: The calculus (integral) is a good example, Leibnitz and Newton "invented" it independently, but Newton tried to discredit Leibnitz, so when I learned in college in the UK they taught it to me as Newton integral, although I later learned in Austria that the method we use nowadays is Leibnitz' and Newtons method was unpractical. Actually, the formal definitions and proofs were given by Riemann and some French and Italians whose names I can't remember. 
Sum and mean of the rectangles under a curve as an approximation of the integral was already used by Babylonians, Egyptians and Greeks even though we are not sure if they already did infinitesimal calculus (Archimedes did, for example contained in the proof the arc length formula). 
Also, I would like to mention that the Pythagorean Theorem was used for centuries before Pythagoras did. The Babylonians also devised an own method of approximation in order to calculate the square roots needed for the Pythagorean theorem. Evidence has been found on clay tablets used probably by Babylonian schoolboys where they had to calculate such things as exercise.
A: Edmonds-Karp's algorithm is actually Dinic's. In addition to that, Dinic found a better running time.
A: Pascal's triangle existed way before him.
The Chinese call it Yang Hui Triangle, not even the first Chinese mathematician to discover it in 11th century.
It was two Persians who first found it in 10th century (i.e. Karaji and Khayyam).
A: Wilson's Theorem may be an example.
A: A proof of the Bolzano–Weierstrass theorem was published by Bolzano about 2 years after Weierstrass was born.
A: L'Hospital's rule was popularized by him but proved by Johann Bernoulli.  Supposedly he paid off Bernoulli to keep quiet.
A: Fermat's last theorem was proved by Andrew Wiles and Richard Taylor. The Poincaré conjecture was proved by Grigori Perelman. Maybe the millennium problems won't change name if they are proved. By the way, I think the name of the theorem also should credit the person who came up with the conjecture since this is also an important part.
A: I think the best example of this is Pell's equation, which was studied and solved by Lord Brouncker. John Pell had literally nothing to do with it, but Euler got the two of them mixed up.
There are plenty of examples of $A$ getting legitimate credit for their own work even though $B$ did it first, or European $A$ getting legitimate credit for work done earlier and independently by Asian $B$, but this is an example of an unconnected person getting entirely undeserved credit through a complete error.
A: Nobody's mentioned the Pythagorean theorem yet?
A: Wilhelm Killing:
To quote Wikipedia:
"
From 1888 to 1890, Killing essentially classified the complex finite dimensional simple Lie algebras, as a requisite step of classifying Lie groups, inventing the notions of a Cartan subalgebra and the Cartan matrix
"
Also Coleman in the greatest mathematical paper of all time says
"By one of those miscarriages of justice which are commonplace in mathematics, most of the fundamental results about Lie algebras which were discovered by Killing are usually attributed to E.Cartan."
and
"
He (Wilhelm Killing) exhibited the characteristic equation of the Weyl group when Weyl was 3 years old and listed the orders of the Coxeter transformation 19 years before Coxeter was born."
Also Killing was the one who introduced the notion of the 'characteristic polynomial' (see this).
A: When I first heard that some people are calling the standard trick from calculus books the Feynman's trick my first impression was WTF?! Are you kidding me?!
Then I saw that more and more people calling the trick known to Leibnitz as the Feynman trick. I knew where it came from, I have read Surely you are joking Mr Feynman?! This might be one of the most preposterious cases illustrating the Stigler's law of eponymy.
The other similar situation is with Glasser's Master Theorem that dates back to Boole, 1857. There isn't yet a Wikipedia or Wolfram article for Feynman's trick, but there is for Glasser's Master Theorem. Boole is not even mentioned in these articles.
A: In his paper Robert Granger argues that the Lucas-Lehmer test could in principle have been discovered by the ancient Greeks. The Miller–Rabin primality test was first discovered by Russian mathematician M. M. Artjuhov in 1967. See: Artjuhov, M. M. (1966–1967), "Certain criteria for primality of numbers connected with the little Fermat theorem", Acta Arithmetica, 12: 355–364.
A: An interesting "inappropriate" credit is for the Diffie-Hellman key exchange, not mentioning Ralph Merkle.
Hellman himself suggested the algorithm be called Diffie–Hellman–Merkle key exchange and has quoted that:
"The system...has since become known as Diffie–Hellman key exchange. While that system was first described in a paper by Diffie and me, it is a public key distribution system, a concept developed by Merkle, and hence should be called 'Diffie–Hellman–Merkle key exchange' if names are to be associated with it. I hope this small pulpit might help in that endeavor to recognize Merkle's equal contribution to the invention of public key cryptography."
I find it very interesting that one of the names of the key exchange actually would like to add another name for credit.
A: *

*The Wiener process, also called Brownian motion, was already known to Louis Bachelier (11 March 1870 – 28 April 1946) who worked on an option pricing theory five years before Einstein published his Brownian motion paper (1905). Norbert Wiener showed among other things the non-differentiability of the Brownian paths in the early 1920-ies.


*An early version of Ito's lemma (1944) was known to Wolfgang Doeblin  (17 March 1915 – 21 June 1940).
A: Newton's relations are two classical identities in the study of symmetric functions. They were derived by Albert Girard in 1629 before Newton was even born.
