The erection of Deer in 1796 has been spoken of. As formed in 1805 the northern boundary of Indiana extended eastward to the mouth of Bull creek. The territory of Deer, as thus reduced, was divided in 1836, under the respective names of East and West Deer. Later in the same year the former was enlarged by the annexation of that part of the present area south of the northern line of Indiana extended, including Springdale township. Fawn and Harrison were also comprised within its limits.

It is believed that the first settler in East Deer was Ezekiel Day. He probably came in 1792, and in 1793 built a cabin and made some improvements. Day’s run was named from him. Prior to 1804 Rev. Abraham Boyd purchased a tract from Mr. Day, and resided there many years. He was pastor of several churches in the vicinity.

Joseph Crawford lived near the mouth of Crawford’s run, which took its name from him. Of his descendants Mrs. Robert Kennedy still resides in the township. Robert Bailey settled on what is now known as Bailey’s run, then called Day’s run. Mr. Bailey, at the age of eighty-four, still resides on the place where he settled, surrounded by his children. James Humes was a settler near the present line between East Deer and Tarentum. The place is still known as the Humes farm, and several of the descendants reside in this vicinity. His wife was a daughter of Mr. Negley. Samuel and James Powell were squatters on adjoining farms near Crawford’s run; none of their descendants are here. Lesley Hazlett and his son George were squatters near the Allegheny river. They were boatmen, and the father was drowned. Solomon Kelsey came prior to 1840, and settled near the Bailey property. James Robertson came to the same place soon afterward. Elias Davis and Stark resided some two miles up Bailey’s run. They were followed by John Ross. Fred. Christ lived on a farm adjoining Mr. Bailey. The widow of his son Fred, now resides in Fawn township. Jesse Brown resided two miles up Bailey’s run, on a portion of the stream which still retains the name of Day’s run. The place is now owned by James Wilson. J. C. Brown, a son of Jesse, was prothonotary of Allegheny county during two terms. He now occupies a prominent position in the municipal government of the city.

Derrick Peterson, a Virginian, was one of the original settlers in East Deer township. He took up large quantities of land here, for which he received patents from the state. Of his children the names are remembered of Lewis, Sr., Peter, Ann (still living), Lydia, wife of Col. James Hite, of Jefferson county, Va., and mother of P. Y. Hite, now of this township ; Lewis Peterson, Jr., was a mayor of Allegheny City. Sprole settled in the upper part of East Deer township, where he died. Samuel Kier succeeded Sprole on the same property. It is worthy of remark that the first petroleum in this region was discovered while drilling for salt on this property, and was accordingly called "Kier’s Petroleum or Rock-Oil."

P. Y. Hite, from whom the village of Hite is named, became a resident of this township in 1857, and engaged extensively in coal-mining and manufacturing salt. His saltworks, which were burned in 1857, were located at the village of Hite. Mr. Hite was also a pioneer oil producer and refiner. Hite is a station on the West Pennsylvania railroad, about one mile from Creighton, and two miles from Tarentum. Prior to 1866 it was only a small hamlet. On the completion of the Pennsylvania railroad it assumed more importance, and now it has, probably, a population of 500. Mining was its principal industry, but since the discovery and utilization of natural gas this has declined. There is a Methodist Episcopal church here. McFetridge Brothers have a brickyard at this place.

Creighton station was established on ground that was a part of the original Peterson estate. It owes its existence to the erection of the plate-glass works there. Kennedy is a station at the lower end of Hite. It was the site of the Central Oil-refinery. The property was purchased from John Kennedy, Sr., in 1872, by a company in Pittsburgh. An extensive refinery was established there and conducted for several years. It was purchased by the Standard Oil company, and discontinued.

In 1860 the population of East Deer was 1,134; in 1870, 1,390; in 1880,. 1,253.