The International Harvester Company was created in 1902 by merging the McCormick Harvesting Machine Company with the Deering Harvester Company, two giants of American farm equipment. Headquartered in Chicago, IH built everything a farm or business needed: tractors, trucks, construction equipment, refrigerators, and one of the most recognised engine ranges of its era.

The 1924 Farmall launched the row-crop tractor era, and the letter series A, B, C, H, and M became fixtures of American agriculture. IH also built the Loadstar and Fleetstar trucks, the Metro delivery van, and the Scout, one of the pioneering sport utility vehicles. The agricultural line became Case IH in 1985, and the truck business continued under the Navistar name from 1986.

IH manuals cover engine overhaul data, ignition and fuel system settings for petrol engines, injection pump timing for diesels, torque specifications, hydraulic and PTO systems, transmission and final drive service, brakes, and complete wiring diagrams for later models. Lubrication charts cover the dozens of grease points these machines carry.

Working farms keeping letter-series and numbered tractors in daily service, Scout restorers, and truck preservationists all depend on factory documentation. IH built its machines to be repaired rather than replaced, and the right manual keeps that philosophy working decades after the dealerships changed their signs. Original books were printed on cheap paper and rarely survived, so digital copies fill the gap.