Marshall Township's existence as a township dates back to June 3, 1863. This territory was previously an election precinct of Franklin Township. Marshall Township is named for Thomas Mercer Marshall, the well-known attorney by whom the proceedings to withdraw from Franklin Township were conducted before the court. For 40 years, in Pittsburgh, there was scarcely an important murder trial in which he did not conduct the defense.

There are two Indian trails dating from the colonial times that wind their way through the area. The Venango Trail cuts the northeast corner of the Township as that historic road follows its course from Pittsburgh to Venango (present day Franklin, Venango County) Erie, and Presque Isle. The Kuskusky Path passes through the entire Township from south to north on its way to Kuskusky (present day New Castle, Lawrence County) and cuts its way through the property where Marshall Elementary and Middle Schools are located.