Charles Oscar Paullin (20 July 1869 – 1 September 1944) was an important naval historian, who made a significant early contribution to the administrative history of the United States Navy.
He then taught mathematics at Kee Mar College in Hagerstown, Maryland, in 1893–94, before beginning his graduate studies at the Johns Hopkins University in 1894–1895.
Naval Hydrographic Office, he also earned a degree in social sciences at the Catholic University of America in 1897.
From 1900 to 1904, Paullin studied at the University of Chicago, where he earned his Ph.D. in 1904 with his pioneer study on the administration of the colonial navy during the Revolution, later published as The Navy of the American Revolution: Its Administration, Its Policy, and its Achievements.
In 1933, Columbia University awarded Paullin and John Kirtland Wright the Loubat Prize for their Atlas of the Historical Geography of the United States (1932).