The 1936–1937 Flint sit-down strike, also known as the General Motors sit-down strike, the great GM sit-down strike, and so on, was a sitdown strike at the General Motors plant in Flint, Michigan, United States. It changed the United Automobile Workers (UAW) from a collection of isolated local unions on the fringes of the industry into a major labor union, and led to the unionization of the domestic automobile industry. Background GM agreed to recognize the UAW as the bargaining agent for workers on February 2, 1937. The agreement was sent by a letter from Knudsen to Murphy in which the GM were agreed for a period of six month after work was resumed to not bargain or even enter into agreements with other employee organization, that letter was referred to the unions on January 4 unless the procedure was sanctioned by Gov. Murphy. (p. 694) The United Automobile Workers (UAW) labor union had only just been formed in 1935 and held its first convention in 1936. Shortly thereafter the union decided it could not survive by organizing campaigns at smaller plants as it had in the past. Instead they would organize automobile workers and go after the biggest and most powerful employer, General Motors Corporation. They would do this by focusing on their most valuable plants in Flint, Michigan. As stated by Henry Kraus, a UAW organizer of the strike, "It was the heart-and-nerve center of the vast combine. Creators of fortunes, incomparable benefactor to the chosen few, prize milch-cow of America's most patrician family, the du Ponts, whose 10,000,000 shares of GM stock assured them a one-fourth cut of the corporation's unabating profits, whatever happened in this central city of the corporation, in this non-descript over-size village, reverberated throughout the financial capitalists of the nation". The importance of these plants cannot be understated, the production plants in Flint were essential to the multiple lines of GM cars, and to the cars of GM's subsidiary companies like Chevrolet and Buick. As explained by Henry Kraus, "The great concentration of autoworkers in Flint was not at the body plants but at Chevrolet and Buick which employed 14,000 and 16,000 men respectively – the largest of all general Motors' 60-odd factories". Another Chevrolet factory, Plant No. 4, would be critical to the sit-down strike as it produced the engines for all Chevrolet cars sold at the time. These plants were vital