Hart-Parr - The Hart-Parr Company was originally formed as the Hart-Parr Engine Works in Madison, Wisconsin by Charles Hart and Charles Parr. In 1900, the decision was made to relocate in Charles City, Iowa. Over the winter of 1901-1902, they produced their first gas traction engine. Hart and Parr were credited for being the first successful mass production gas traction engine company. They are also credited with introducing the word "Tractor" to the English language. By 1907, the Hart-Parr Company was well established in the tractor manufacturing business and had six major branch houses, as well as an evergrowing factory in Charles City. World War I was not a profitable time for Hart-Parr, since they lost a lot of money retooling for the manufacture of munitions. Existing problems caused Charles Hart to leave the company in 1917. Charles Parr remained with the company until his death in 1941. The Hart-Parr Company merged with the Oliver Chilled Plow Works in 1929 to form the Oliver Farm Equipment Company.

Oliver Chilled Plow Works - In 1855, James Oliver of Mishiwaka, Indiana bought 1/4 interest in a small foundry outside of South Bend. In 1857, he received his first patent for his chilled plow. This chilled plow had a very hard outer skin and was able to scour in heavy, sticky soils with greater wearability. Word of its success spread world-wide, resulting in an enormous amount of plows being manufactured and sold. Oliver soon became known as the "Plowmaker for the World." In the 1920's, Oliver began experimenting with a tractor of their own. The result was the "Oliver Chilled Plow Tractor." Only one example of this tractor is known to exist today. Shortly after their tractor venture, Oliver merged with Hart-Parr, who already was set up in the tractor business. A new line of tractors was produced using ideas from the Chilled Plow tractor and Hart-Parr's past experience.

Oliver Farm Equipment Company - This Company was formed in 1929 after the merger of Hart-Parr Tractor Works, Nichols & Shepard, Oliver Chilled Plow Works, and the American Seeding Company. Corporate offices were set up in Chicago, Illinois while the plants remained at their existing locations. The company could now supply the farmer with a tractor, tillage tools, planting tools, and harvesting machines. The Oliver Farm Equipment Company became the Oliver Corporation in 1944.

Cletrac - Cleveland, Ohio continued to produce a full line of crawlers with world-wide exports. Their horsepower range varied from 9 Hp up to their hefty 100 Hp model. In 1944, Cletrac was acquired by the Oliver Corporation. Crawler production continued until 1962 when White Motor Corporation purchased Oliver. At that time the crawler production was relocated to Charles City, Iowa. It remained there until production was discontinued in 1965. Between 1916 and 1944, there were approximately 75 different crawler models.

White Motor Corporation - In 1960, White Motors acquired the Oliver Corporation as a wholly-owned subsidiary. In 1962, they acquired Cockshutt of Canada, and in 1963 ,they also acquired Minneapolis-Moline. In 1969, White Motor Corporation combined its Oliver and Minneapolis-Moline subsidiaries to become the White Farm Equipment Company with headquarters at Oak Brook, Illinois. White Motor Corp. acted as the parent company of the White Farm Equipment Company and continued to exist until the farm equipment division was sold to TIC in 1980, and the truck division was sold to Volvo in 1981. The last Oliver green tractor to roll off the assembly line bearing the Oliver name was in 1976 with the 2255 designation.

Oliver Motor Hart Parr
Oliver 55
3 digit series