The town was founded in 1865 in the Lower Bari Doab country and named Montgomery after Robert Montgomery, Lieutenant Governor of the Punjab. It was renamed Sahiwal in 1966 after the Sahiwal cattle of the district.
The Sahiwal is a red-brown zebu, heat tolerant, tick resistant and one of the best dairy breeds of the subcontinent. It has been exported to Kenya, Australia, the Caribbean and Brazil, and is used worldwide to cross into local stock. The breed carries the name of a Punjab town in the herd books of a dozen countries.
Harappa is in this district, on an old bed of the Ravi, and was largely dismantled in the 1850s when its brick was taken for ballast on the Lahore to Multan railway. What survives was excavated from what the contractors left.
The district also holds Pakpattan, the shrine of Baba Farid Ji, about seventy kilometres south.
The breed's home tract is the bar country between the Ravi and the Sutlej, where it was kept by pastoralists before the canals arrived, and it was selected for milk under conditions that would kill a European animal.
The Lower Bari Doab Colony was among the last of the canal colonies, settled from about 1913, and its villages are numbered chaks on the same system as Lyallpur's.
Harappa is in this district. The site was quarried for railway ballast in the nineteenth century before anybody knew what it was.