 Docking emigrated to America and settled in Kansas with his parents, Robert Docking and Martha Mynott, in 1876.Docking chose to direct his missionary efforts towards Native American populations, first in Oklahoma (then called Indian Territory), where he worked as a superintendent of Spencer Academy in the town of Nelson.During the years 1891-1893 Docking and his wife, Anna Allen Marshall, taught at the Sitka Training School, a Presbyterian missionary school for Indian boys and girls at Sitka, Alaska.