Twin Mounds Cemetery began around 1890 or 1891, before the Dawes Commission and statehood, when "Uncle Dump" Berryhill, a part Creek Indian and Holiness preacher, donated five acres for a burial ground because a man had died and there were no local cemeteries and no mortician. The first grave was covered with piled stones to keep cattle away, and some of those stones still remain. The cemetery contains 3,300 grave sites, only 500 of them marked, and information has been recovered for people buried in several graves. Many of the dead were infants because vaccinations and doctors were lacking, and as the area’s only cemetery it became the burial place for many early pioneers, including the mother of Slew Thompson of Thompson Ranch and Oil of Beggs, while Glenpool and Kiefer continued using it because they never established cemeteries. During the Depression, burials here were free, and few families had money for permanent markers. After oil was discovered in 1905 on the Ida Glenn allotment at the northeast corner of 141st Street and Highway 75, setting off a boom that lasted several years, Martha Boling, whose quarter section included the cemetery, had signed an oil lease on the tract, but when drillers tried to enter the burial ground, Berryhill camped there for several days with a 30-30 rifle across his knees and refused to let them move into the cemetery. The nearby community of Twin Mounds, first called Posey after Creek poet Alex Posey, originally stood on the high ground between the two mounds about 3/4 mile northeast, then moved twice to reach the railroad before becoming Mounds about five miles southwest. Three Twin Mounds schools were also located here: the first stood just north and slightly west along a small creek, the second one-half mile north at the southwest corner of 161st Street and the county line, and the third just east of the south mound, on a spot later covered by the new Highway 75. Gilcrease family allotments lay mainly in the section immediately south, with Thomas Gilcrease’s allotment about one-half mile north of the cemetery around the south end of the north mound, and the father’s allotment at the southeast corner of the section to the south, where he built a cotton gin later moved to Leonard, Oklahoma.