American Tractor Corporation (ATC) was started when the Rojtman family purchased a factory in Churubusco, Indiana, USA. After researching US and German army tanks and crawlers, ATC began producing crawler-tractors under the TerraTrac brand. In late 1956, Case merged with ATC. ATC formed the core of Case's crawler and industrial line. By the late 1960s, Case shifted all production to Burlington, Iowa, USA and sold the Churubusco factory.