First, Turing was awesome and what was done to him by the British government was criminal.
However, three brilliant Poles cracked Enigma long before Turing did. Those Poles were Marian Rejewski, Henryk Zygalski and Jerzy Różycki. As much as I enjoy reading and learning about Turing's early work with electric computers, the work Rejewski did with his team was even more impressive to me.
You can read more about these unsung heroes here.