This is a timeline for the Battle of the Atlantic (1939–1945) in World War II.
OB 293 was a North Atlantic convoy which ran during the battle of the Atlantic in World War II. It was notable for seeing the loss to the Kriegsmarine (KM) of U-47, with her commander KL Günther Prien, the person responsible for the sinking of HMS Royal Oak two years previously.
Convoy SC 42 was the 42nd of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. SC 42 was attacked over a three night period in September 1941, losing 16 ships sunk and 4 damaged. This was the worst Allied loss following the attack on convoy SC 7 the previous year. Two attacking U-boats were destroyed.
Convoy SC 104 was the 104th of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. During October 1942, a U-boat wolf pack sank eight ships from the convoy. The convoy escorts sank two of the attacking submarines.
Convoy SL 125 was the 125th of the numbered series of World War II SL convoys of merchant ships from Sierra Leone to Liverpool. Ships carrying commodities bound to the British Isles from South America, Africa, and the Indian Ocean travelled independently to Freetown, Sierra Leone, to be convoyed for the last leg of their voyage. Thirty-seven merchant ships departed Freetown on 16 October 1942 and were joined at sea by five more.
SS Beatus was a British cargo steamship that was built in 1925, sailed in a number of transatlantic convoys in 1940 and was sunk by a U-boat that October.
HMS Arabis was a Flower-class corvette of the Royal Navy. The ship was commissioned into the Royal Navy as HMS Arabis. She was transferred to the United States Navy in 1942, serving as USS Saucy. Returned to the United Kingdom in 1945, she was recommissioned into the Royal Navy as HMS Snapdragon.
HX 72 was a North Atlantic convoy of the HX series which ran during the battle of the Atlantic in World War II. The convoy comprised 43 ships of which 11 were sunk and another damaged by German U-boats who suffered no losses.
SC 129 was a North Atlantic convoy of the SC series which ran during the Battle of the Atlantic in World War II. It was one of several convoy battles that occurred during the crisis month of May 1943.
HX 237 was a North Atlantic convoy of the HX series which ran during the Battle of the Atlantic in World War II. It was one of several convoy battles that occurred during the crisis month of May 1943.
Convoy ON 122 was a trade convoy of merchant ships during the Second World War. It was the 122nd of the numbered series of ON convoys Outbound from the British Isles to North America. The ships departed Liverpool on 15 August 1942 and were joined on 17 August by Escort Group B6 of the Mid-Ocean Escort Force.
Convoy HX 126 was the 126th of the numbered series of World War II HX convoys of merchant ships from HalifaX to Liverpool.
Convoy HX 65 was a North Atlantic convoy of the HX series which ran during the battle of the Atlantic in World War II. It was the 65th of the numbered series of merchant convoys run by the Allies from Halifax to Liverpool. The convoy was attacked by German U-boats and aircraft, losing eight of its 51 ships sunk and a further three damaged. One U-boat was damaged.
Convoy HX 231 was the 231st of the numbered series of Second World War HX convoys of merchant ships from HalifaX to Liverpool. The ships departed New York City on 25 March 1943 and were met on 31 March by Mid-Ocean Escort Force Group B-7. The convoy was found on 4 April and attacked by eleven U-boats of the 1st, 3rd, 6th and 10th U-boat flotillas, from Brest, La Rochelle, St Nazaire and Lorient, respectively. These U-boats formed wolfpack Löwenherz' (Lionheart). The U-boats sank six ships before losing contact on 7 April. Two U-boats, U-632 and U-635, were sunk. The convoy reached Liverpool on 10 April.
Convoy SC 100 was a North Atlantic convoy, one of the SC series which ran during the battle of the Atlantic in World War II. It was the 100th of the numbered series of slow convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. It came under attack, one of several convoy battles that occurred during the autumn and winter of 1942, losing five ships.
Convoy ON-153 was the 153rd of the numbered series of ON convoys of merchant ships Outbound from the British Isles to North America. The World War II convoy departed Liverpool on 11 December 1942 and was met on 12 December by Mid-Ocean Escort Force Group B-7. Two merchant ships and the escort group leader were sunk in a North Atlantic battle with U-boat Wolf pack Raufbold before reaching the Western Ocean Meeting Point (WOMP) where the Western Local Escort Force assumed responsibility for the convoy on 23 December. Surviving ships reached New York City on 31 December.
Prien's wolfpack is the name given in some sources to a formation of German U-boats that operated during the Battle of the Atlantic in World War II. It existed from 12 June to 17 June 1940.
Convoy HX 49 was a North Atlantic convoy of the HX series which ran during the Battle of the Atlantic in World War II. It was the 49th of the numbered series of merchant convoys run by the Allies from Halifax to Liverpool. The convoy was attacked by German U-boats, losing three of its 50 ships sunk. Another ship was lost after dispersal.
HMS Hibiscus was a Flower-class corvette, built for the Royal Navy during the Second World War, and was in service in the Battle of the Atlantic. In 1942 she was transferred to the United States Navy as part of the Reverse Lend-Lease arrangement and renamed USS Spry, one of the Temptress-class gunboats. With the end of hostilities she was returned to the Royal Navy and sold into mercantile service.
HMS Periwinkle was a Flower-class corvette, built for the Royal Navy during the Second World War, and was in service in the Battle of the Atlantic. In 1942 she was transferred to the United States Navy as part of the Reverse Lend-Lease arrangement and renamed USS Restless, one of the Temptress-class gunboats. With the end of hostilities she was returned to the Royal Navy and sold into mercantile service.
Germany 
United Kingdom 
