The American Locomotive Company was formed in 1901 by the merger of Schenectady Locomotive Engine Manufactory of Schenectady, New York with seven smaller locomotive manufacturers.
The other companies that merged were Brooks Locomotive Works in Dunkirk, New York, Cooke Locomotive and Machine Works in Paterson, New Jersey, Dickson Manufacturing Company in Scranton, Pennsylvania, Manchester Locomotive Works in Manchester, New Hampshire, Pittsburgh Locomotive and Car Works in Pittsburgh, Pennsylvania, Rhode Island Locomotive Works in Providence, Rhode Island, Richmond Locomotive Works in Richmond, Virginia.
Baldwin was the largest manufacturer and Alco was the second-largest steam locomotive manufacturer in the US, producing over 75,000 locomotives. Aloc’s locomotives were both steam and diesel. Many of these locomotives were well-known. Railroads that favored Alco products included the Delaware & Hudson Railway, the New York, New Haven & Hartford Railroad, the New York Central Railroad, the Union Pacific Railroad and the Southern Pacific.
Alco was known for its steam locomotives of which the 4-6-4 Hudson, 4-8-2 Mohawk and the 4-8-4 Niagara built for the New York Central and the 4-8-4 FEF and the 4-6-6-4 (Challenger) built for the Union Pacific were examples.
Alco built some of the biggest locomotives ever constructed, including Union Pacific’s Big Boy (4-8-8-4). Alco also built the fastest American locomotives, the Class A Atlantic and Class F7 Hudson streamliners for the Milwaukee Road’s Twin Cities Hiawatha run. Alco produced narrow gauge locomotives built for the military service behind the trenches of World War I
During World War II, Alco produced many 2-10-0 Decapods for the USSR. Joseph Burroughs Ennis was a senior vice president between 1917 and 1947 and was responsible for the design of many of the locomotives manufactured.
ALCO subsidiaries also manufactured automobiles and nuclear power for a short period. Alco was purchased in 1964 by the Worthington Corporation and merged with the Studebaker corporation in 1967 to form Studebaker-Worthington, Inc. Locomotive production ended in 1969.
Micro-Mark carries many Alco locomotives: http://www.micromark.com/search?keywords=Alco