Mary Ann Dawson was born in Des Moines, Polk County, Iowa, to her father Dr. N. M. Hansen and mother Anna Hansen. She married John Hamilton Dawson, whom she had known since East High School, on April 2, 1950. With a major in nursing, she visited Korea on October 10, 1963 with her husband and children as a missionary for the Northern Presbyterian U.S.A.

Mary Dawson came to Dongsan Christian Hospital with her husband as a missionary, worked as a nurse, and devoted herself. And she devoted her heart to the care of his husband and children. In addition, she actively participated in the ministry of the missionary department of the Northern Presbyterian U.S.A. and devoted herself to teaching the Bible and teaching Sunday school. They also organized an English class for missionary children and taught them every day.

After three years of missionary work at Dongsan Christian Hospital from 1963 to 1966, she returned to the United States with her family.

Dr. and Mrs. John Dawson at Dongsan Christian Hospital, 1966

John Dawson's Family (John Dawson, Mary Dawson, Stephen, Mark, Peter, David), 1963