Edward London Campbell, who was called Gammuyeol, was born and raised in the U.S. and graduated from the University of Washington. His wife Elizabeth Ellen Campbell first visited Korea in 1913 as a missionary for the Northern Presbyterian U.S.A. and Campbell visited Korea on September 18, 1914.

He was an industrial missionary with reasonable methods and expertise in various fields such as carpentry, farm practice, ironworks, ranch management, pig farming, and architecture. He taught poor students and transferred skills at Soongsil School in Pyongyang, contributing greatly to the development of the school as well as self-reliance. From 1915 to 1916, a total of 93 students helped themselves to fund their own tuition.

Dongsan Christian Hospital began building a hospital building in 1930 with a fund sponsored by Northern Presbyterian U.S.A. At this time, Campbell, who had expertise in architecture, came down to Daegu and stayed for three months to help Fletcher to prevent and solve various problems by supplementing the hospital's detailed design drawings in detail.

For the hospital's foundation work, bricks were piled up to make concrete floors, and a slab flat roof was made of concrete. In addition, iron window frames were made and built, and electrical facilities were installed.

Campbell returned to the United States in 1833 after completing all his missionary duties and lived in Seattle, Washington, U.S.