James Hamilton Ballagh

James H. Ballagh (1832–1920) was an American missionary who was instrumental in introducing Protestant Christianity to Japan.

Early life Ballagh's parents, John Hamilton Ballagh and Anne Prudencia Craig, had immigrated from Ireland to the United States, eventually settling in Hobart, New York, where he and his ten siblings were born. They were initially Presbyterians but later converted to the Dutch Reformed Church.

After reading about the need for missionaries, he was inspired to become one himself. He attended Rutgers University before completing study at the New Brunswick Theological Seminary in 1860.

The couple shared a compound with other missionaries such as Samuel Robbins Brown and James Curtis Hepburn and discreetly promoted their religion in spite of its illegal status in Japan at the time. They worked to translate the Gospel of John with the help of Rizuan Yano, who Ballagh later baptized in the earliest Protestant Christian baptism in Japan.

A major 1866 fire in the Yokohama settlement destroyed the initial translations, but Ballagh, Hepburn, and another missionary, David Thompson, worked to remake the translation. Hepburn completed the translation of that and other Gospels. They had three daughters and a son.