Reverend William Hawley, the second Rector of St. John's, baptized and married African Americans of all legal statuses when he led the Church from 1817 to 1845. Many of these marriages took place in the Rector's own home, adjacent to the Church, with his wife and family as witnesses. According to the marriage register of St. John's, Reverend Hawley performed weddings for 6 couples identified as "slaves," 38 identified as "colored," and 2 identified as "colored (free)." For example, on January 11, 1828, the Reverend Hawley married Emmeline Matthews, listed as "colored" to William Prates, listed as a slave. The very next marriage he performed was for John Quincy Adams' son John and his bride Mary Hellen. A selected transcription is available.

In 1865, the Rector of St. John's worked with a group of 28 African Americans to establish a new Episcopal church. A member of St. John's donated land in the Foggy Bottom area of Washington for the construction of a church building, which was named St. Mary's Chapel for Colored People in 1867. Six years later, St. Mary's hired its first African-American rector, Alexander Crummell.

In August 1963, there was uncertainty among some in the city regarding the upcoming March on Washington for Jobs and Freedom. St John's rector, Rev. John C. Harper, was cautioned by church wardens to avoid dissension within the church by staying away and closing St. John's doors as "it might be a bloodbath." Rev. Harper was encouraged by a young curate, Rev. H. Vance Johnson, to do just the opposite. Rev. Harper not only kept the church open, but St. John's also planned to hold a prayer service representing their denomination as part of a call from interdenominational church councils to support the march and its participants. At 11:00 a.m. on August 28, a special service of prayer was held with 700 participants of all races filling St. John's. Afterwards, Rev. Harper sent a letter to his parishioners stating his support for Dr. King and St. John's future policy: "…This church building is open, as it has always been, to all who want to worship here; the ministry of this parish is extended to any who seek it; our fellowship with one another has no limitations whatsoever."

Selected Entries from the St. John's Church Marriage Register

Reverend Hawley sometimes recorded African American couples' race and whether they were enslaved or free. Often, the register simply identifies people as "colored," which may have meant that he was not sure of their legal status. Some of the weddings listed are:

• "Henry Butler, slave of Captain John Rodgers, and Susan Smith, slave of George Graham, Esquire. May 3, 1827. Witnesses: Mr. Graham's family and friends. At Mr. Graham's. Colored."
• "Thaddeus Hughes, slave of Colonel Tayloe, and Kitty Thomas, slave of Mrs. Jos. Baker. February 2, 1826. Witnesses: the Reverend Hawley's family. At the Reverend Hawley's."
• "John, slave of Colonel Tayloe, and Winny, slave of Mrs. Kedglie. October 3, 1822. Witnesses: the Reverend Hawley's Family. At the Reverend Hawley's."
• "David Hall and Sidney A. Neil. April 4, 1819. Witnesses: Emily Chisholm and Susan King. At the Reverend Hawley's. Colored."

Civil Rights Era at St John's Church

Though African Americans had been married by St. John's rector in the 1840s, in 1960, the church had no African-American members. As the Civil Rights Movement gathered force, the Church leadership recognized the need to actively welcome parishioners of all races. In August 1963, the same month that saw the March on Washington for Jobs and Freedom during which the Reverend Martin Luther King, Jr. made his "I Have a Dream" speech, St. John's Reverend John C. Harper sent a letter to his parishioners that read, "This church building is open, as it has always been, to all who want to worship here; the ministry of this parish is extended to any who seek it; our fellowship one with another has no limitations whatsoever." On the day of the March on Washington, over 700 people meeting for the march filled St. John's.