About 1810, Adam Mohney and wife of Northampton County bought 1600 acres of land in Clarion County from the Holland Land Company. This piece of land was bounded on the north by Pine Run, east by Red Bank Creek, south by Oak Ridge, and west by Town Run. The land was divided among friends and relatives. Jake Mohney, a nephew of Adam, bought 500 acres of the land where Hawthorn now stands and built his home there. After the death of Mr. Mohney, some of the land was purchased by W. C. Sloan and laid out in lots.

The first store was built by James Kerr in 1830. In it was installed the first post office and the settlement became Kerr’s Station. There was talk of building a grist mill, so the little settlement was made into a town and called Millville. The grist mill was not built, and there was another Millville in Pennsylvania, so to avoid confusion the name was changed to West Millville.

The first borough ordinance, containing 22 articles, was drawn up in 1882. In 1907, a house was purchased and voted to be used as a Council House and Jail. The same building is used for that purpose today. Before the building of the Low Grade Railroad, West Millville was the chief shopping place for teamsters hauling merchandise from Mahoning to Brookville. Mr. John Cribbs erected a large hotel in 1904 for the accommodation of these teamsters. Two hotels were built soon after.

In March, 1873, the Low Grade Railroad was completed through Clarion County. James McWilliams was the agent in West Millville. In 1904 the Railroad Company set in a box car for a station. A bridge connecting Armstrong and Clarion counties, was built across the Red Bank Creek in 1878. This was washed out by a flood and replaced in 1903 by an iron bridge.

The industries of Hawthorn belong almost exclusively to the past. In 1893, a pottery was started by Arblaster, and was run until 1923. A canning factory was organized in 1900 and was in existence about two years. The only source of employment is in the Wallwork Coal Mines, which began operating in 1921.

In 1869, a draft for the independent school district of West Millville was drawn and the first school was built the same year. It was replaced by a two-room building in 1885. The same building with two additions is now used for eight grades and a four year high school.

There are three churches: the Evangelical built in 1873, the Presbyterian, built in 1876, the Methodist, built in 1886. In 1932, a Nazarene Church was started in the Methodist Church building.

The name of the town, West Millville, was changed to Hawthorn by David McCargo, a Scotch railroader. He named it for the shrub of the same name that grows in Scotland.