Mount Pleasant Township was founded on April 6, 1773 as one of the eleven original townships of the newly created Westmoreland County.
The first officers elected by the people of the township were: Constable, John McClelland, Overseers of the Poor, Solomon and John Sheppard and Supervisor John Scott.
When the first settlers came to the township, they found it occupied by roving Indian bands with temporary villages and camps, but no permanent villages.
The first settlers were mostly young men of German descent. In the 1790's, the total taxable inhabitants were 378, but nearly twice that number were believed to exist who either rented lands or worked for landowners.
After the early settlers cleared their lands and built log houses, farming was the principal occupation. The rich limestone clay soil raised good crops, chiefly grains. Later, large brick houses were built as a symbol of permanency.
One of the early industries was an iron furnace operated by William Freeman in the area now known as Freeman Falls. In addition to the smelting of iron ore, cannon balls were produced for the War of 1812.
Another furnace was built around 1810 in Jacobs Creek by Alexander McClurg, but was blown out in 1820. The furnaces and the sites are no longer in existence as the Pennsylvania Turnpike now passes directly over the spot.
Other industries were tanneries and distilleries that made whiskey, which was transported by broad wheeled wagons over the mountains east to Philadelphia and Baltimore. It was more profitable to ship grain in distilled alcohol form over the mountains than it was to ship the bulk grain, which was just as obtainable from the broad fertile farmland of the Lancaster area.
The principal town in the township, Mount Pleasant, now a borough, was also settled in 1770, three years before the establishment of Westmoreland County. It became a borough in 1828. The main east-west route through the Chestnut Ridge ran through the township from Donegal through Acme (on a road built of wood planks, hence Plank Road) and down Three Mile Hill to Laurelville. Although the hill is only two miles long, it is rumored that wagon drivers said it felt more like three miles because of the steepness of it. At the bottom of the hill is located the scenic town of Laurelville, still one of the prettiest areas of the township. There was located a house of entertainement, one of the earliest buildings in town, owned by the Lobinger family. Jacob Lobinger was a noted miller, taking advantage of the waterpower of Jacobs Creek. He was also an industrialist and store owner as well as the Postmaster of Laurelville for twenty-five years.
By 1870, the population of the township had burgeoned to 2,547 of which 2,492 were native born and 55 of which were foreign and presumably black.
In the early days of the township there were many clay pikes, so named because the clay base was easy on the feet of the animals that hauled the goods. The present day Clay Pike, as we know it, extends from Kecksburg to Route 31 at Brady's Restaurant and Leeper's store, east of Acme. Acme is so named because it was the highest point in the township. The first schoolhouse on record was located along the Clay Pike. Later, a two-room frame building was erected along Route 31, now known as the Acme Community Center. Many of the hamlets and small towns were named after the person who owned the store in the area, since it was common practice for the storekeeper to be the mailman and postmaster.
Calumet derived its name from the French word "chalumet", which means reed or pipe type object. The Indians used these 'peace pipes' to signify all-important occasions, particularly when dealing with the white man.
In 1788, inhabitants of the eastern part of Mount Pleasant Township, thinking the township was too large, petitioned the court to create a new township for that area lying in proximity to Loyalhanna Creek. The boundary bisected the town of Lycippus, an old Greek name, was chosen because the original name of Mount Union was already taken in the eastern part of the state.
The original high school, known as Hurst High School, was built in 1905 and added onto in 1928. It is now the site of Electroglass Products, a major employer in the township. Hecla, founded in 1905 and named after Henry Clay Frick, is also known for mail purposes as Southwest. The Sewickley Brance of the Pennsylvania Railroad ran through Hecla to transport shipments of coke, as well as providing passenger service.
Norvelt, started as a federal project, is the youngest community in the Township, and derived its name from Eleanor Roosevelt, who made this Westmoreland Homesteads her pet project.
Kecksburg was so named because of the Keck family who settled there for the commercialization of the Artesian spring water. They later bottled and sold a variety of soft drinks including the famous Keck's Ginger Ale.
The name United derives from the United Coal and Coke Company, which owned adjacent mines.
The largest coal mine in the world at the time was located in Mammoth, hence the name.