The idea for St. Gregory the Great Parish began on August 22, 1957, when the Diocese of Buffalo purchased a 22.75-acre tract of farmland from Mrs. Katherine Klein. The property was located on Maple Road, a two-lane country highway that ran through a portion of the town of Amherst. The following year, in June 1958, Bishop Joseph A. Burke appointed Rev. Robert L. Buchheit as the first pastor of what would become a new parish on that isolated piece of farmland. Father Buchheit's dream of a new parish and the enthusiastic support of his parishioners sustained him through the winter of 1958, when snow blew through cracks in the walls and windows of the farmhouse rectory. In July of the following summer, parishioners gathered for a field Mass to bless and dedicate the land where a new school and rectory would be erected.
Thirteen months later, on September 7, 1960, the dream became reality with the grand opening of St. Gregory the Great School with 386 students, who were taught by the Sisters of St. Francis and several dedicated lay teachers. The school building also served as the parish church, with Masses taking place in classrooms until the installation of an altar and pews transformed the school auditorium into a temporary church. The solemn Dedication of the School and the new Rectory took place on October 16, 1960 with Bishop Burke presiding.
In 1967, construction began on the current church and a much-needed addition to the school. The Solemn Dedication of the Church took place on October 13, 1968 with Bishop James A. McNulty presiding. By this time, the parish had grown to about 1600 families. From that point on, rapid growth characterized both the Amherst area and St. Gregory the Great Parish. The parish community has grown to well over 13,000 parishioners and over 5,000 families. Over the years additions to the parish campus have included a playground, expanded parking lots, new landscaping, grotto, café and catholic store.