Eastern Sea Frontier

The Eastern Sea Frontier (EASTSEAFRON) was a United States Navy operational command during World War II, that was responsible for the coastal waters from Canada to Jacksonville, Florida, extending out for a nominal distance of two hundred miles. The Commander was designated Commander, Eastern Sea Frontier (COMEASTSEAFRON). COMEASTSEAFRON had vessels for convoy use or other uses determined by the commander. In addition to providing escorts for convoys within its frontier, the frontier was responsible for sea-air rescue, harbor defense, shipping lane patrol, minesweeping, and air operations.

Although the Code of Federal Regulations indicate Eastern Sea Frontier's commander also served as commander of the Atlantic Reserve Fleet as of 1937–38;

On 14 January 1941, orders were issued to transfer Rear Admiral Andrews from his command as Commander, Scouting Force, United States Fleet to a new command as Commandant, Third Naval District. These orders were modified under date of 1 March 1941, giving Admiral Andrews additional duties as Commander, North Atlantic Naval Coastal Frontier. When he relieved Rear Admiral C. H. Woodward on 10 March 1941 for the first time the Commandant, Third Naval District was also designated as Commander, North Atlantic Naval Coastal Frontier.

The preparation of operation plans, which had been laid down in WPL-42 and in Navy Basic War Plan, RAINBOW No. 3 (PL-44), the latter having been promulgated in December 1940 was continued and on 16 March 1941 the first Operation Plan: North Atlantic Naval Coastal Frontier Plan 0–4 (RAINBOW 3), with the short title, NA-NCF-44 was issued. This Plan set up the proposed Staff of the Commander, North Atlantic Naval Coastal Frontier, which consisted of the following: Chief of Staff, Operations Officer, Shipping Control Officer, Air Officer, First Army Liaison Officer Intelligence Officer and Communication Officer. It also provided for the Command Relations and the plans for coordination with the Army Commander. Nevertheless, at this time, no officers were immediately available to fill these commands.

On 3 April 1941, a second plan was issued to modify NA-NCF-44 in such a way as to make it applicable to the concept of war outlined in "RAINBOW No. 1." This modification was entitled, North Atlantic Naval Coastal Frontier Plan O-4 (RAINBOW No. 1), with the short title, NA-NCF-42. On 22 April 1941, a third plan was issued: the original Operation Plan for the Forces of the North Atlantic Naval Coastal Frontier. This plan was designated, "Operation Plan, NA-NCF-1-41." Because of the restricted nature of problems concerned with the organization of task forces and task groups within a naval coastal frontier, this aspect is considered in a separate section. It may suffice to state briefly, here, that at this time, task forces were not created. When the Navy Basic War Plan, RAINBOW No. 2 (WPL-46) was issued in May 1941, important directives were contained therein as to the eventual organization of task forces and command relations in the naval coastal frontiers; nevertheless, these directives merely outline the structure of an organization which would not be created until a later order was issued.

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