Under the office of the Provost Marshal General the Selective Service System was made up of 52 states (or territories) and 4,648 local boards. These organizations were responsible for registering men, classifying them, taking into consideration needs for manpower in certain industries and in agriculture, as well as certain special family situations of the registrants; handling any appeals of these classifications; determining the medical fitness of individual registrants; determining the order in which registrants would be called; calling registrants; and placing them on trains to training centers.
District boards were established by the President (one or more for each Federal Judical District). The average district board had jurisdiction over approximately 30 local boards, each with an average registration of 5,000 men. The district boards had appellate jurisdiction over the decision of local boards in some claims and original jurisdiction in others.
Local boards were established for each county or similar subdivision in each state, and for each 30,000 persons (approximately) in each city or county with a population over 30,000. The local boards were charged with the registration, determination of order and serial numbers, classification, call and entrainment of draftees.
During World War I there were three registrations. The first, on June 5, 1917, was for all men between the ages of 21 and 31. The second, on June 5, 1918, registered those who attained age 21 after June 5, 1917. (A supplemental registration was held on August 24, 1918, for those becoming 21 years old after June 5, 1918. This was included in the second registration.) The third registration was held on September 12, 1918, for men age 18 through 45.
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