The history of St. Mary's United Methodist Church parallels the early development of the South Union addition of the Sunnyside area. Since no Methodist Church existed in the area in 1949, the Board of Missions at Trinity East Methodist Church, under the leadership of Rev. Luther B. Felder, canvassed the neighborhood on Sunday evenings to find a site for a new church. Trinity East also contributed to the project financially by collecting donations from its members on the fourth Sunday of each month. The site for the future church, on the corner of Nathaniel Brown and Corder Street, was donated by Mrs. Mary Issacs, a devoted Methodist and educator in the Houston Independent School District. Rev. Edwin S. Harrison, a member of Trinity East and a beginning minister, was assigned to be St. Mary's first pastor. With him came his wife and two daughters. The Harrisons and others walked through the community on a daily basis looking for prospective members. Dr. and Mrs. A. B. Jordan both took a leave of absence from Trinity East and became the first members of St. Mary's. The Jordans gave their time, talent and finances to support the Harrisons in erecting a building and remained faithful members until 1953. The relocation of St. Mary's to its present site occurred in 1966 under the guidance of Bishop Noah W. Moore, Jr., District Superintendent Robert E. Hayes, Sr. and Rev. F. W. Logan. The church grew rapidly under the leadership of Rev. Robert E. Felder and Associate Pastor Earl Allen, Sr. Simon Snell, Joseph Cox and Andrew Harris followed.
Rev. Felder and the church continued to grow. Rev. L.V. Winfield served as interim pastor after the death of Rev. Andrew Harris in 1977 and helped the church to become financially stable.
In May of 1977, Rev. Earl Allen, Sr. was reappointed to St. Mary's as the senior pastor. True to expectations of the membership, Rev. Allen, with the assistance of Rev. Kirbyjon Caldwell, worked diligently to improve the physical appearance of the church and to increase its membership. Rev. Allen was followed by
Rev. Herbert Liedy in 1984. Following the brief tenure of Rev. Leidy, Rev. Noel Lark was appointed in November of the same year.
Rev. Robert Hayes was appointed to St. Mary's as the senior pastor in June 1986. Under his leadership. The church progressed in many areas, especially financially. Rev. Thomas E. Wallace was appointed in June 1990. Under his leadership, the church experienced a renewed vibrancy and spirituality.
Rev. Robert Jackson came to St. Mary's in October of 1995. One of the highlights of his ministry was the formation of the Shalom Zone Program. This ministry provided many services for the church and the community.
Rev. J.D. Brown was appointed to St. Mary's in 1998. New ministries added during his leadership were Our Daily Bread, Meals on Wheels, Mary's Garden, and the Food and Clothing Pantry.
Rev. Thomas Walker was appointed in January 2005. His leadership provided many changes at St. Mary's such as sanctuary renovations, renovation of bathrooms, fellowship hall and church entrance. Also established were the Children's Church and Nursery ministry in addition to partnering with Foster Elementary and Cullen Middle School.
Pastor Leo Tyler was appointed to St. Mary's in June 2012. Through his sermons on stewardship commitment, he inspired members to tithe and increase offerings to the church. This enabled the Finance Committee to achieve fiscal success in several areas. Some accomplishments with Pastor Leo’s leadership included reopening the food pantry to provide both spiritual and physical nourishment to both the church and community. “We provided food for over 10,000 individuals in the last 12 months.” Pastor Leo would often say, “At St. Mary's we are always getting better.”
Pastor Keith Bell was appointed to St. Mary's in July 2015. In his tenure he showed a love for ministry and for God's people. Pastor Bell implemented evening Bible Study, Project Samuel (After School Program), and Young Adult Ministry that focused on the generational growth of the church looking forward to new ministries and great things to come.
Rev. Johnnie Simpson, Jr. was appointed to St. Mary's in July 2023. Pastor Simpson envisions working with the congregation and increasing the church's impact on the community as well as the city.