A contributor to the field of tropical and parasitic diseases for a full half-century, Charles Franklin Craig probably made a more distinctive impress on students of American tropical medicine than any of his colleagues and associates. Born in Danbury, Connecticut, the son of a country physician and educated at Yale, he received his medical degree from that institution in 1894 when laboratory medicine was relatively young. In 1898 he became a contract assistant surgeon with the United States Army, first at Sternberg General Hospital (Chicamauga Park, Georgia), then successively at Simpson General Hospital (Fortress Monroe, Virginia), Camp Columbia Hospital (Havana, Cuba) and the Army General Hospital (Presidio, California). During the last of these assignments, in 1903, he began his long service as a regular Army officer, starting as 1st lieutenant and receiving regular promotions until he attained the rank of colonel in 1918.

Craig's tours of duty were fortunate ones for American tropical medicine: in Manila (1906–07) with the Army Board for the Study of Tropical Diseases, at El Paso (1916–17),in Hawaii (1922–26),at Ft. Leavenworth (1907–09,1913–16 and 1917–18),and in Washington with the Army Medical Museum and the Army Medical School (1909–13,1919–22)and later, as Director of the Army Medical School (1926–30) and Assistant Commandant of the Army Medical Center (1930–31)