Having served as a military chaplain in Manila, Hermon Williams saw the need for missionaries to be sent. Writing to the Foreign Christian Missionary Society, he expressed this need. In response, they asked him and his wife, Beulah Williams, to consider going. They arrived in the fall of 1901 and set about learning Spanish and engaging in evangelism. Through their work, thousands of Gospels, New Testaments, tracts, and hymnals were distributed. Mr. Williams conducted preaching services and Bible study classes in Spanish up to six times a week.

In October 1905, Mr. and Mrs. Bruce L. Kershner arrived in Manila as the next missionaries to join the effort. Mr. Kershner immediately immersed himself in the work, beginning intensive study of both Spanish and Tagalog to better serve the mission and communicate with local communities. Early on, he began training young men preparing for ministry, offering courses in the Gospels, Christian Doctrine, Apostolic and Old Testament History, and foundational biblical teaching, all taught in English. Alongside his teaching, he also preached regularly in Manila and nearby provinces.

Leslie Wolfe and Carrie Wolfe arrived in Manila on October 29, 1907. While in Manila, they consistently labored in the Lord’s work, engaging in evangelism, teaching, and strengthening the growing churches associated with the Restoration Movement. During their ministry, they also faced and responded to theological and practical tensions within the broader movement, including opposition from denominational influences and debates surrounding “open membership.” Through preaching, teaching, and steady church work, they remained committed to building congregations centered on New Testament teaching and encouraging faithfulness among local believers.

In this year the Foreign Christian Missionary Society (FCMS) of the Restoration Movement was reorganized into the United Christian Missionary Society (UCMS). This change was not simply a renaming, but a major consolidation of several mission-related agencies within the movement, being dominated by the Disciples of Christ. Along with the FCMS, other bodies such as the American Christian Missionary Society, the Christian Women’s Board of Missions, and various church extension and service boards were brought under one centralized organization to coordinate both domestic and foreign mission work.

Faustino Peneyra came to faith in Christ in 1908 through the evangelism of John Lord, who was serving in Vigan at the time. After completing his studies at a Bible training school, Peneyra began preaching the gospel and quickly became active in evangelistic work. In 1923, he was invited to move to Aparri to serve as minister of the Aparri Church of Christ. His dedicated and tireless efforts in evangelism among his fellow Filipinos played a significant role in the spread of churches throughout the northern region of the Cagayan Valley.

On April 30, the Wolfes resigned from the United Christian Missionary Society due to theological differences over liberalism and “open membership.” With no financial support from the UCMS, their work in the Philippines seemed to be coming to an end. That evening, representatives from the major churches in Manila, after days of prayer and fasting, approached the Wolfes. They offered to share their salaries with Leslie and Carrie if they would stay and continue their work. Earlier that day, a telegram had arrived from the Christian Restoration Association, pledging the first year of salary. This marked the beginning of the Philippine Mission Churches of Christ, the first direct-support mission efforts of its kind.

What began as a great undertaking in 1901 came to a quiet end. Through comity understandings between the Methodist Church and the United Christian Missionary Society, mission work in northwestern Luzon gradually shifted. By the 1940s, Protestant presence in areas such as Vigan, Laoag, and Aparri had largely been given to the Methodist, as the United Christian Missionary Society efforts were withdrawn and property sold off. Later, parts of the Disciples of Christ wing of the Restoration Movement participated in the broader Protestant union movement, joining with the Evangelical Church in the Philippines, the Philippine Methodist Church, the United Evangelical Church, and segments of the Presbyterian Church to form the United Church of Christ in the Philippines (UCCP).

When the Japanese invaded the Philippines during World War II, missionaries and other foreign nationals were eventually interned in concentration camps. More than 2,000 men, women, and children were confined under increasingly harsh conditions, with limited space and dwindling rations. In early 1945, the camps were liberated by elements of the U.S. Army’s 11th Airborne Division, working alongside Filipino guerrilla forces, with the rescue of prisoners achieved without loss of life among those being held. Just over a month after liberation, on March 26, 1945, Leslie Wolfe died as a result of the severe conditions endured during internment by the Imperial Japanese forces. He was buried in the land he served at the Manila American Cemetery and Memorial, Plot D, Row 12, Grave 192.

At the end of 1946, Faustino Peneyra issued a “Macedonian Call” through the *Restoration Herald*, seeking additional workers for the field. In 1947, Charles Selby and Roberta Selby responded to that call and arrived in Aparri with their young son, Lloyd. Over the years, their ministry grew alongside their family life. The Selbys devoted themselves to strengthening local congregations, training emerging leaders, and supporting the expanding Church of Christ work throughout northern Cagayan Valley. Their efforts worked in harmony with those of earlier laborers, including Faustino Peneyra and Leslie Wolfe, helping lay a foundation for sustained church growth across the region.

Mrs. Wolfe had sent letters to Cincinnati Bible College seeking young men or families willing to become missionaries in the Philippines. Barton and Betty McElroy answered the call and arrived with their three children (Barbara, Jeannie and Jimmy) that year. They quickly joined in at Manila Bible Seminary and Barton headed the "Church Planting" endevour.

Aparri Bible Seminary (ABS) was established. ABS began training preachers and teachers and launched a rapidly expanding evangelistic program of Bible training seminars, preaching meetings, a Christian kindergarten, VBS programs and youth camps.

Norval and Dondena Campbell joined the workin Aparri, with Norval’s expertise as a college educator playing a key role in establishing strong academic standards and structure at Aparri Bible Seminary. Dondena's background in music helped Roberta with the music curriculum and other aspects of the seminary.

Aparri Christian Press was launched to print Christian periodicals and other much-needed materials for church ministry and evangelism in both English and the Ilocano language.

After several years of losing their young men to the Aparri Bible Seminary where they would meet a nice young lady and setting in the Cagayan region, the leaders of the churches on the northwestern side of Luzon appealed to establish a seminary. The Campbells rose to the challenge and established the Philippine Bible Seminary in Vigan.

Sid and Marj Boudreaux arrived with their children, and served for 20 years. Marj taught and worked with many programs at ABS, and Sid fulfilled the difficult role of operational logistics.

The dream of Benjamin Dugay Sr. and Charles Selby, through God’s remarkable provision, Northern Isabela Academy opened its doors in 1967.

Trusting God’s provision as he had with previous ministry buildings, Charles Selby initiated construction by faith. He hired teams to lay the foundation, and remarkably, donations and supplies arrived exactly as needed for each stage. By God’s grace, SIA opened its doors to students in 1967, simultaneously with NIA.

Charles Selby and his son, Lloyd, stepped forward in faith as the mission bought more land to expand. Moved by God, U.S. supporters gave generously, providing all that was needed. Guided by Lloyd, construction began, and by June 1986, Central Isabela Christian Academy (CICA) opened to students.

In 1998, the Aparri Christian Hospital was opened to the community. In the early 2000's the Board of Directors voted to rename the Charles W. Selby Memorial Hospital.

In 2023, Charles W. Selby Memorial Hospital celebrated 25 years of outstanding service to the Aparri community and surrounding areas. Under the leadership of Administrator Ofelia “Pia” Tabilisima, the hospital has risen to become the number one healthcare facility in the region.