Bedford Township was formed in 1767 within Cumberland County. Then, in 1775, Frankstown Township was formed out of the northern third of Bedford Township, along with a portion of Barre Township. In 1785, Woodberry Township was formed out of the southern part of Frankstown Township along with an additional small portion of Bedford Township.
In 1794, St. Clair Township was formed from a portion of Bedford Township; it was located adjacent to the western half of Woodberry and bordered along that township’s southern boundary. In 1798, that western part of Woodberry Township (lying to the west of Dunnings Mountain range, between it and the Allegheny Mountain range) was separated to be formed into Greenfield Township.
Thirty-six years after the formation of Greenfield Township, and forty after St. Clair Township was formed, Greenfield was divided in two along an east-west line and St. Clair was divided similarly in two along an east-west line although, in both cases, the two halves were not the same size. The southern third of Greenfield and the northern quarter of St. Clair were combined into a new township that was named: Union. In 1846, when Blair County was erected out of Huntingdon and Bedford, the remaining two-thirds of Greenfield were absorbed into the new county. The entire region that had been formed as Union remained under the jurisdiction of Bedford County.
Union Township would undergo its first division in 1876. Divided into two unequally sized parts, the western half retained the name, while the eastern half was given the name: King Township. King Township as it stands in the 21st Century includes only the southern two-fifths of its 1876 size. The township of Kimmel was formed in 1889 from the northern three-fifths of King Township.
King Township was named in honor of Alexander King. Alexander King was the President-Judge for the Sixteenth District between June 1864 and January 1871. Judge King had started as a lawyer in the 1840s. In 1834 King, along with fellow lawyer, John Mower, purchased the Democratic Inquirer, for which he was co-editor for four years.
An early settler of this region was Christian King. He and his family resided along the west bank of Gap Run on lands that in 1877 were identified as belonging to D. Gochenour. Christian, his wife, and infant son and a young girl that lived with the family were attacked by and taken captive by the Amerindians in the pre-Revolutionary war days. The four were eventually released and made their ways back to their homestead. Although wrong, it is often believed that the township was named for Christian King.