Bloch worked at the French Aeronautics Research Laboratory at Chalais-Meudon during World War I and invented a type of aircraft propeller subsequently used by the French army during the conflict. In 1916, with Henry Potez and Louis Coroller, he formed a company, the Société d'Études Aéronautiques to produce the SEA series of fighters. In 1928 Bloch founded the aircraft company Société des Avions Marcel Bloch, which produced its first aircraft in 1930. In 1935 Bloch and Henry Potez entered into an agreement to buy Société Aérienne Bordelaise. In 1936 the company was nationalized as the Société Nationale de Constructions Aéronautiques du Sud Ouest. Bloch agreed to become the delegated administrator of the Minister for Air. During the occupation of France by Nazi Germany during World War II, France’s aviation industry was virtually disbanded, other than the compulsory manufacturing, assembly and servicing of German designs. In October 1940, Bloch refused to collaborate with the Germans occupiers at Bordeaux-Aéronautique and was imprisoned by the Vichy government. In 1944 the Nazis deported Bloch to the Buchenwald concentration camp, as punishment for refusing to co-operate with their regime. He was tortured and beaten and held in solitary confinement. In the meantime his wife was interned near Paris. Bloch was detained at Buchenwald until it was liberated on 11 April 1945. By the time of his return to Paris he was crippled to such an extent that he could barely walk. He was advised by his doctors to settle his affairs, as they did not expect him to recover his health. After the war he changed his name from Bloch to Bloch-Dassault and in 1949 to Dassault. Dassault was the nom de guerre used by his brother, General Darius Paul Bloch, when he served in the French resistance, and is derived from char d'assaut, French for "battle tank". In 1971 Dassault acquired Breguet, forming Avions Marcel Dassault-Breguet Aviation.
Personal life
In 1919, Bloch married Madeleine Minckes, the daughter of a wealthy Jewish family of furniture dealers. They had two sons, Claude and Serge. After changing his name to Dassault, he converted to Roman Catholicism in 1950. In July 1952, Dassault acquired the Paris landmark buildings now known as Hôtel Marcel Dassault, dating from 1844, at nos. 7 and 9 rond-point des Champs-Elysées, from the Sabatier d'Espeyran family. The building at no. 7 has been used since 2002 by the auction houseArtcurial, which had further alterations made under the direction of architect Jean-Michel Wilmotte. While no. 7 has been sold, no. 9 is still used by the Groupe Industriel Marcel Dassault.
