Elder Mark E. Petersen was ordained an apostle and set apart as a member of the Council of the Twelve on April 20, 1944, by President Heber J. Grant, reported the April 23, 1944, issue of the Church News.
The new apostle had been sustained on April 6, 1944, during the opening session of the 114th Annual General Conference.Elder Petersen was the 12th apostle called since President Grant became president of the Church in 1918. He was general manager of the Deseret News and first counselor in the presidency of the Sugar House Stake at the time of his call.
Speaking briefly at general conference the day following his sustaining, Elder Petersen said: "I have never felt so humble in all my days as I do at this present moment. I am indeed grateful for the gospel of Jesus Christ. I am most happy that the Lord permitted me to be born in a Latter-day Saint home where my parents taught me to believe in the message which they had received in a foreign land, the message which I shall bear to all the world through the rest of my life."