Founding of The American Legion
"No one can lay claim to originating the idea of a veterans' association, because it was a concensus among the men of the armed forces of our nation." - George S. Wheat, The Story of The American Legion, 1919
A few months before his discharge from the Army, D’Olier received orders to go to Paris in February 1919 to serve on a board for improving morale among the AEF, whose first and foremost wish was to get home.
In Paris, he met with Theodore Roosevelt, Jr. and a group of 18 other officers, including George A. White, William "Wild Bill" Donovan, future Undersecretary of the Treasury Ogden L. Mills and David M. Goodrich.
The group made suggestions for improving morale that the Army General Headquarters (GHQ) later implemented, with some modifications.
After their official deliberations concluded, Roosevelt invited the group to dinner to discuss the formation of a post-war veterans' organization and laid plans for a caucus to be held in Paris in March.
This group of 20 laid the foundation for the organization that would become The American Legion.
After participating in the early discussions, D’Olier returned to his original assignment as a supply officer at Bordeaux, leaving the work of organizing a caucus, obtaining permission from GHQ and drumming up interest among the soldiers of the AEF to George A. White of GHQ, Eric Fisher Wood of the Army’s 88th Division, and Ralph D. Cole of the Army’s 37th Division, though Cole quickly dropped out of the effort.
Several AEF publications printed news of the upcoming caucus, including the Camp Dodger, a newspaper published by Eric Fisher Wood's 88th Division.
D’Olier attended the Paris Caucus as a delegate, describing himself as an “inconspicuous member of that notable assemblage” who contributed nothing.