Where did the code breaking happen for the Enigma machine?

Answer 1

Polish cryptanalysts working in Warsaw, Poland first broke the German Army Enigma and built a simple electromechanical Bombe machine in spring of 1939. However when the Germans invaded on September 1, 1939 they had to flee Poland. Initially going to France, but when France was invaded in 1940 the Polish cryptanalysts went to England. There they became part of the team at Bletchley Park.

The British team at Bletchley Park had been stymied by Enigma until the Poles arrived, bringing with them a stolen German Army Enigma machine (which answered several questions the British had). Bletchley Park eventually designed larger more advanced and powerful Bombe machines which they used throughout the war to read Enigma messages.

Several times the Germans made improvements to the Enigma (especially the Navy Enigma) forcing the British to have to break the cypher again, sometimes even involving capturing another Enigma machine to see what those changes were. The most difficult change to break was the addition of a 4th rotor to the Navy Enigma, which could only be handled by the addition of a high speed vacuum tube electronic box to the side of the electromechanical Bombe machine.

Answer 2

The Enigma Code was cracked by mathematicians at Bletchley Park in Buckinghamshire.