Trinity United Presbyterian Church was the first United Presbyterian Church in Southern California. It was organized by 18 Charter Members on June 22, 1876, in the home of James McFadden. The Reverend D. S. McHenry was the first pastor in 1878 and the first sanctuary was built on the northwest corner of 4th and Mortimer Streets in Santa Ana. A year later the Reverend T. J. C. Webster was called by the congregation at a salary of $600 a year. The population of Santa Ana then was about 700.

The years moved by and in 1895 the Reverend M. M. Kilpatrick was installed as a pastor and in 1903 several members withdrew from the church because the elders voted to use a piano in the worship service. Later the Reverend W. L. C. Sampson was minister and during his pastorate a new sanctuary was built on the northwest corner of 6th and Bush Streets in Santa Ana. Several years later Dr. J. C. Kennedy served as a pastor, Dr. W. H. McPeak next, and then Dr. Albert A. Kelly.

In 1946, Dr. M. DeWitt Safford came as the minister after four years as chaplain in the Navy in the South Pacific. The church membership jumped to about 500 members. The post-war growth continued during the pastorate of Dr. Harold E. Scott.

In 1958, the present location of about nine acres was purchased for $6,400 per acre. A year later, the Reverend George A. Munzing began his pastorate at Trinity. The last service at 6th and Bush was held on November 4, 1962 and the Reverend Donn Moomaw was the guest speaker.

A week later the first services were held in our new chapel. In 1967 our inspiring sanctuary was completed. The Reverend George Munzing served Trinity for 37 ½ years until his retirement in April, 1997. Gary Demerest served as Interim Pastor for two years and on August 1, 1999, the Rev. Dr. Alan Landes began his Ministry here until September, 2003. Dr. Douglas J. Rumford joined Trinity in November 2006 and is currently serving as our Senior Pastor and Rev. Roger Purdy is our Interim Associate Pastor. Our current membership is approximately 1,270.

God has blessed our church in its growth and its witnessing over the years and we thank Him for it. We welcome every new member into this Church Family.