Calvin Coolidge to work jointly with Edward T. Clark, a Massachusetts Republican organizer whom he retained from his vice-presidential staff, as Secretaries to the President (a position equivalent to the modern White House Chief of Staff). Perhaps the most powerful person in Coolidge's Cabinet was Secretary of the Treasury Andrew Mellon, who controlled the administration's financial policies and was regarded by many, including House Minority Leader John Nance Garner, as more powerful than Coolidge himself. Secretary of Commerce Herbert Hoover also held a prominent place in Coolidge's Cabinet, in part because Coolidge found value in Hoover's ability to win positive publicity with
Sherman Coolidge the 1940s. In September 1915, Reverend Coolidge, speaking as President of the Society, appealed for recognition of American Indians as citizens and called upon the country to observe a national "American Indian Day." In response, President Calvin Coolidge issued a proclamation on September 28, 1915, which declared the second Saturday of each May as American Indian Day. Reverend Coolidge traveled throughout United States making addresses and delivering lectures on behalf of the Society and American Indians. In May 1923, Coolidge and other society leaders joined with reformer John Collier founding the American Indian Defense Association, a powerful new lobby in