Neuromancer: The history of Einstein and Quantum Theory is more interesting than you might suspect.
In the first few years after the Planck paper on black body radiation, Einstein stated that Planck & other physicists did not understand the implications of Planck's results. He stated that they were assuming something analogous to oscillators being responsible for the quantum effects. Einstein claimed that the results implied that energy was a quantum phenomenon.
Almost without exception, the physicists of that era claimed that Einstein had literally lost his mind. A friend wrote a letter saying that he should be forgiven for his flight of fantasy in consideration of his other important work. Einstein wrote several papers, including the one on the photoelectric effect for which he got his Nobel prize. After his papers and various discussions, the world of physics acknowledged that he was correct.
BTW: He said the following about the controversy. (paraphrase, not an exact quote)
When the current controversy is resolved, the Swiss will proudly mention that I am a Swiss citizen and the Germans will brag about me being a German. Meanwhile, the Swiss call me a German and the Germans call me a Jew.
Many consider Einstein more important than Planck in initiating quantum theory. After the theory became well established by others, Einstein disagreed with the probabilistic nature of it and what he called
spooky action at a distance. He never really disagreed with the Uncertainty Principle and various other aspects of the theory.
It is interesting to note that neither Einstein nor anybody else ever received a Nobel prize for Relativity. It is my understanding that there was an unwritten rule that nobody could receive two Nobel prizes in one category. Einstein was deliberately given his prize for the photoelectric effect (a quantum phenomenon) rather than for Relativity in order to acknowledge his contributions to Quantum Theory and to apologize on behalf of those who called him crazy for advocating quantized energy. The committee felt that he would always be acknowledged as a genius for General Relativity, making a prize in that category superfluous, while they felt that he might not be given as much credit as he deserved for his contributions to Quantum theory.
Many remember his losing Quantum Theory debates with Bohr. Few remember that he was one of the founders of Quantum Theory.