1918–1931
After her shakedown in New England waters, R-1 was assigned to Submarine Division 9 of the Atlantic Fleet, and based at New London, Connecticut. She got underway on 4 December 1919, for Norfolk, Virginia, and winter exercises with her division in the Gulf of Mexico, and returned to New London, on 18 May 1920, for four months of summer operations with R-2 and R-3, before sailing on 13 September, for Norfolk and overhaul.
When the US Navy adopted its hull classification system on 17 July 1920, she received the hull number SS-78.
R-1 was ordered to the Pacific Ocean, on 11 April 1921. She transited the Panama Canal, in late May, and arrived on 30 June, at her new base, San Pedro, California. She took part in fleet exercises off Central America, from 5 February through 6 April 1923, and returned to San Pedro, on 10 April. On 16 July, she was transferred, along with Division 9, to Pearl Harbor. For the next eight years she trained crews and developed submarine tactics out of Pearl Harbor.
Departing San Diego, California, on 5 January 1931, R-1 sailed for Philadelphia, Pennsylvania, via the Panama Canal, and arrived on 9 February. She was decommissioned there on 1 May.
1940–1946
On 23 September 1940, R-1 was recommissioned, in ordinary, at Groton, Connecticut. She was overhauled and commissioned in full, on 16 October. R-1 got underway with Submarine Squadron 3, Division 42, on 10 December, for the Panama Canal Zone. She was stationed at Coco Solo, for a year, then she was reassigned to Division 31, in June 1941. R-1 was ordered to New London, in October, for a refit, and transferred to Squadron 7.
At New London, on 7 December 1941, R-1 remained in the southern New England area for the first days of the United States participation in World War II. On 9 and 10 December, she patrolled the sealanes leading to New England, and on 11 December, arrived at Bermuda, whence, with other SubRon 7 boats, she joined the hunt for U-boats preying on maritime traffic along the Atlantic Seaboard. Although limited in cruising range, the R-boats operating out of Ordnance Island, Bermuda, continued their patrols through the Kriegsmarine submarine offensive of early 1942.
In February, the submarines established a patrol line between Bermuda and Nantucket Island. On that patrol line, some 300 nautical miles (560 km; 350 mi) northeast of Bermuda, R-1 sighted and fired four torpedoes at the surfaced U-boat, U-582, and was credited with sinking the German submarine, although U-582 was in fact undamaged.
R-1 continued patrols out of Bermuda, until returning to New London, on 20 July, for upkeep and coastal patrols. At the end of September, she resumed operations out of Bermuda. Through November 1944, she rotated between Bermuda and New London, and at the latter, in December, underwent an extensive conversion to enable her to participate in the development of anti-submarine warfare (ASW) equipment and tactics. Emerging from the yard on 26 February 1945, she steamed to New York City, on 28 February; then headed south to Florida, for three weeks of operations off Port Everglades, Florida. In April, she returned to New London, then on to Casco Bay, Maine, for further ASW tests. Returning to the Thames River base, on 29 June, she headed south again on 7 July, and at mid-month, reported for duty with the Fleet Sonar School at Key West, Florida, where she served for the remainder of her career.
United States
