After World War Two, the breeding of horses for reproduction in the Province of Olsztyn grew on what had remained from the East Prussian infrastructure. The first State Stallion Stud was opened (on the initiative of the State Horse Rearing Stations) in Ketrzyn as late as in 1947, and the delay was due to the extensive war damage and the slow process of building of the Polish administration. The catchment area served by that stud covered nearly half of the province. Four years later, in response to the progressing post-war reconstruction, intensive growth of state-owned farms and farmers’ cooperatives, another stallion stud was created in Braniewo. The formation of both studs was greatly aided by the State Stallion Stud in Kwidzyn. Horses from the two studs in the Province of Olsztyn were used for work in farming, for transport as well as for recreation and sports horse riding. Some of the horses could also be seen in historical films. However, the technological progress in farming gradually depreciated the role of horses, which led to a decline in horse breeding. After a few decades, it caused the collapse of the State Stallion Studs in Warmia and Mazury.