Having completed shakedown, Ludlow left Boston in October 1941 for Newfoundland and Iceland, convoying supplies ultimately destined for the British Isles. The 7 December attack on Pearl Harbor and the declaration of war between Germany and the United States soon lengthened Ludlow’s convoy runs to include the ports of Londonderry, Liverpool, Greenoch and Freetown, South Africa.
Assigned to Task Force 34 for the invasion of North Africa, Ludlow arrived off Cape Fedhala, French Morocco late on 7 November 1942. Shortly after the first wave of landing craft headed for shore, Ludlow found herself engaging shore batteries, bombers and a Vichy French naval force comprised of a cruiser and two destroyers. A 8-inch shell struck her forward and straddling shots were falling close aboard when Augusta and Brooklyn arrived and helped to dispose of the French ships.
The “Lucky Lud” returned to New York to repair battle damage and then conducted training off the coast of Maine before departing 14 January 1943 for the first of three convoy runs to Casablanca. After the third of these, in June, she remained in the Mediterranean for the forthcoming invasion of Sicily. With the invasion forces on 10 July, Ludlow gave fire support off Licata and Porto Empedocle. Daily enemy air attacks followed and on 11 August she splashed her first airplane.
Participating in the invasion of Italy on 9 September, Ludlow led a section of the assault wave through a known minefield to the bloody landing at Salerno. She and her sister ships were warmly commended by the commanding general ashore for their effective close-range fire support. She then served on convoy duty between Naples and Oran until 11 January 1944. Returning to the beachheads, she covered Allied troops storming ashore at Anzio 22 January. This joint American-British operation initially met little opposition, but later in the day the Germans struck with a fierce counterattack. Heavy air attacks marked the following days and in less than a week, Ludlow splashed two bombers, one fighter and three rocket glider bombs. A 6-inch shell crashed through the torpedo director deck and the pilothouse, causing Ludlow to retire; but serious damage was averted when Chief Gunner’s Mate James D. Johnson located the hot, unexploded shell and managed to get it topside and overboard.
Ludlow was repaired at New York and then trained along the Atlantic coast and returned to the Mediterranean 20 April for antisubmarine patrols. On 19 May Ludlow and Niblack depth charged U-960 to the surface, where Ludlow’s main battery sank her.
After convoy assignments in the western Mediterranean, Ludlow steamed 11 August from Palermo for the invasion of southern France. Following preinvasion bombardment and beachhead screening off Frejus, she joined Augusta 25 to 30 August to help overcome the last resistance at Marseilles. While on coastal fire support missions around Monaco, she encountered not only floating mines and S-boats, but also attacks by explosive-laden boats and human torpedoes. Ludlow captured three operators of these one-man diving machines on 5 September after a series of depth charge attacks. Fire support, convoy and patrol duty continued until 23 January 1945, when Ludlow sailed for a month’s plane guard duty off the west coast of Africa, returning to Boston 28 February. In April she sailed to England to escort a convoy of LSTs stateside, then prepared for duty in the Pacific.
Transiting the Panama Canal 27 June, she reached Pearl Harbor on 17 July and began training for operations with the fast carriers. The surrender of Japan, however, diverted her to the job of escorting ships filled with occupation troops to the home islands of the defeated Empire. She departed Pearl Harbor on 7 September and arrived at Wakayama, Japan on the 27th. Ludlow operated in the Far East until 3 November and then sailed for the Aleutians where she saw a brief period of “Magic Carpet” duty.
Early in 1946, Ludlow was ordered back to the East Coast, and on 20 May 1946 she was placed out of commission in reserve at Charleston, South Carolina. After this she was utilized for Reserve training. She was placed in commission in reserve on 6 June 1950 and on 21 November of the same year she was placed on active status. Ludlow decommissioned on 22 January 1951 and was transferred to the Royal Hellenic (Greek) Navy, which renamed her HHMS Doxa.
Ludlow earned six service stars during World War II.