[3] In July, 1918, Captain D'Olier was ordered to Lyon, France, to organize the second large depot, which at the time of the armistice had a capacity of taking care of salvaging for upward of a million and a half men.

After his discharge from the service, D'Olier joined Theodore Roosevelt Jr., who was at that time—early in 1919—perfecting the preliminary organization of The American Legion in the United States preparatory to the St. Louis caucus, May 8, 9 and 10.

[3] After the St. Louis caucus he was placed in charge of the State Organization Division at national headquarters, 19 West 44th Street, Manhattan, New York City, and gave his entire time without any remuneration whatsoever to American Legion work in preparation for the Minneapolis convention.

[4] In 1944 in answer to a request by Secretary of War Stimson, D'Olier organized and directed the United States Strategic Bombing Survey.

This group of observers and technicians worked in both the European and Pacific theaters of war gathering data on the effectiveness of air bombardment "upon the will and capacity of the enemy to resist."