During the last quarter of the nineteenth century, many Danish and Norwegian Christians immigrated to the United States, including New Haven, CT. Many of these believers had been part of the lay revival movements in their homelands. In 1882 Lars Haubro started preaching in a rented hall at 201 Orange Street in New Haven. Soon after, in 1887, the "Danish Evangelical Free Church" was formed with thirty-two charter members. In 1900 the name was changed to "The Danish-Norwegian Evangelical Free Church."

The first church building was located in New Haven on Cedar Street (1903-1923), then Elm and Platt Streets (1923-1972), and finally, at its present location on Center Road in nearby Woodbridge.

During the early years of the church, all services were conducted in the Danish-Norwegian language. This continued until 1910 when the Young People's Services and the Sunday School were conducted in English. In 1934 the name was changed to "The Evangelical Free Church of New Haven, Connecticut," and English was used for all services.

Trinity Church is a member of the EFCA, The Evangelical Free Church of America. Trinity is also listed with the Evangelical Free Church New England District Association.

The Evangelical Free Church of America was formed in 1950 by the merger of two church bodies: the Swedish Evangelical Free Church and the Norwegian-Danish Evangelical Free Church Association. Both groups had been birthed in the revival movements of the late nineteenth century.

The Swedish group had its formal beginnings in Boone, Iowa, at a conference held in October of 1884. In that same year, two Norwegian-Danish groups began to worship and fellowship together in Boston, Massachusetts and Tacoma, Washington. By 1912, both the Swedish Evangelical Free Church and the Norwegian-Danish Evangelical Free Church Association had been formed.

Those two associations, representing 275 local congregations, were formally joined together as they gathered for a merger conference in June of 1950 at the Medicine Lake Conference Grounds near Minneapolis, Minnesota. The international and national offices of the EFCA have been located in Minneapolis since the merger took place.

Today, the Evangelical Free Church of America is an association of over 1,300 autonomous churches united by a mutual commitment to serve our Lord Jesus Christ with the guidance of the Holy Spirit and obedience to the Word of God. We are committed to cooperate with one another in ministry and fellowship as we seek to fulfill the Great Commission which Christ has entrusted to His Church. The growing ministry of the EFCA currently extends to some 45 countries of the world.