The passing of Mountfort Mills on April 24, 1949, deprived the American Baha'i community of the influence and experience of a very distinguished believer. He had been a follower of Baha'u'llah since 1906.
Before the end of 1909, Mountfort Mills had made two pilgrimages to 'Akka. His third pilgrimage to visit the Master was made early in 1921. In 1922, with Mr. Roy C. Wilhelm, he was invited by Shoghi Effendi to go to Haifa for conference with the Guardian on matters related to the new conditions created for the Faith by the Ascension of 'Abdu'l-Baha.
During the Master's visits in New York during 1912, Mr. Mills served on the Baha'i reception committee which arranged public addresses for 'Abdu'lBaha in that city. First chairman of the National Spiritual Assembly of the Baha'is of the United States and Canada when formed in 1922 in accordance with the provisions of the Will and Testament left by the Master, Mountfort Mills was elected a member of that body for seven terms between 1922 and 1937. As trustee of Baha'i Temple Unity he had served annually from its inception in 1909.