Marian Rejewski (pronounced "MAHR-yahn Rey-EFF-ski) was born on 16 August 1905 in Bydgoszcz, Poland.
He was a mathematics graduate of Poznan University who, as a student, had attended a cryptology course organized by the Polish General Staff's Cipher Bureau.
He joined the Biuro Szyfrow (Cipher Bureau) of Polish Military Intelligence in September 1932. There he studied ways of cracking the German Army's Enigma cipher machine, which had come into service in 1930.
His achievements jump-started British reading of Enigma in World War II and the intelligence so gained may have substantially altered the course of the war.
Rejewski fundamentally advanced cryptanalysis by applying pure mathematics - permutation theory - to break the Enigma cipher for the first time.
Previous methods had exploited patterns and statistics in natural language texts such as letter-frequency analysis. Rejewski's mathematical techniques, combined with material supplied by French military intelligence, enabled him to develop methods of breaking the periodic as well as individual keys used in encrypting messages on the Enigma machine.
Rejewski devised a mathematical theorem that wartime Bletchley Park luminary, Professor IJ Good, has described as "the mathematical theorem that won World War II."
Details of the Polish achievements were revealed to British and French intelligence representatives in a meeting at a secret Polish Cipher Bureau facility at Pyry, in the Kabaty Woods south of Warsaw, on 25 July 1939.
The Germans had made changes to Enigma equipment and procedures in 1938 and 1939 that increased the difficulty of breaking messages; and as it became clear that war was imminent and Polish resources would not suffice to optimally keep pace with the evolution of Enigma encryption, the Polish General Staff and government had decided to bring their western allies into the secret.
With the crucial Polish contribution of reconstructed sight-unseen German Enigma machines and the Poles' cryptological techniques and equipment, the British at Bletchley Park, and later the Americans, were able to continue the work of breaking German Army, Air Force, Nazi Party SD, and (though with substantially greater difficulty) Naval Enigma traffic.
In September 1939, after the outbreak of World War II, Rejewski and his fellow Cipher Bureau workers were evacuated from Poland via Romania to France. At "PC Bruno," outside Paris, they continued their work at breaking Enigma ciphers, collaborating by teletype with their opposite numbers at Bletchley
Park.
When "Bruno" was evacuated upon Germany's invasion of France, the Polish cryptologists and their ancillary staff worked for two years in unoccupied southern (Vichy) France and outside of Algiers in French North Africa.
Following the German takeover of the "Free Zone" in November 1942, the secret French-Polish "Cadix" center in southern France was evacuated. Its Polish military chiefs were captured and imprisoned by the Germans but protected the secret of Enigma decryption.
Rozycki, the youngest of the three mathematicians, had died in the January 1942 sinking of a French passenger ship as he was returning from a stint in Algeria to "Cadix" in southern France.
Rejewski and Zygalski fled France for Spain, where they were arrested and imprisoned for three months. Released upon the intervention of the Polish Red Cross, almost three months later, in July 1943, they made it to Portugal; from there, aboard the HMS Scottish, to Gibraltar; and thence, aboard an old Dakota, to Britain.
Here Rejewski and Zygalski were inducted as privates into the Polish Army (they would eventually be promoted to lieutenant) and employed at cracking German SS and SD hand ciphers.
After the war, Zygalski remained in Britain while Rejewski took a big risk and returned to Poland to reunite with his wife and two children. He worked as a bookkeeper at a factory-bringing disfavor on himself when he discovered irregularities-until his retirement, and was silent about his work before and during the war until, in the 1970's, he contacted the military historian Wladyslaw Kozaczuk.
He published a number of papers on his cryptological work and contributed generously to books on the subject.
Rejewski died on 13 February 1980 in Warsaw and was buried at the Powazki Cemetery, one of Poland's pantheons of the great and valiant.
The Polish Mathematical Society has honored him with a special medal.
An odd footnote to the story of Rejewski's cryptologic contributions is that his role in World War II had been so obscure that one best-selling book (William Stevenson's A Man Called Intrepid, 1976) not only did not credit him with the work he had done but identified him as "Mademoiselle Marian Rewjeski."
