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Protecting our Nation's Interests

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Battle of the Atlantic

IN May 2013 the 70th anniversary of the Battle of the Atlantic (BOA 70) will be commemorated with a series of events centred around the cities of Liverpool, London and Derry-Londonderry.

The Battle of the Atlantic was the longest continuous military campaign in World War 2, at its height from mid-1940 through to the end of 1943. The BOA demonstrated the enduring importance of control of the sea to provide a highway for the transport of raw materials, munitions, and men, to maintain the nation’s security and to project power across the globe. The Battle of the Atlantic was pivotal to the success of the allied side in World War 2. After the fall of Europe, the main supply route for the continued prosecution of the war was between north America and the UK across the North Atlantic. Ultimately it was the successful protection of this vital sea corridor by British and allied ships from the German surface and U-boat threat that led to success in North Africa, at D-Day and ultimately resulted in the fall of Germany.

Next event


Date: 23rd - 31st July
Events taking place across the UK to mark the 70th anniversary

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Outbreak of War

September 1939 - May 1940

The Battle of the Atlantic raged across the years of World War 2; the North Atlantic was an essential route for trade vessels and warships to support the Allies
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    The Convoy System

    By October 1939 the convoy system was fully in force
    • Oct1939
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    HMS Courageous

    Aircraft Carrier sunk by U-Boat off south west Ireland
    • 17 SepSunk
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    HMS Royal Oak

    The Mighty Oak was sunk by U-Boat in Scapa Flow
    • 14 Oct1939
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    Invasion of Norway

    U-Boats withdrawn from Atlantic to focus on Norwegian Campaign
    • Apr1940
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    SS Athenia

    First British ship sunk by U-Boat in World War 2
    • 3 Sep1939
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    U-12 and U-40

    U-Boats sunk by the Dover Barrage in October 1939
    • Oct1939
    • U-12 Sunk
    • U-40 Sunk
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    U-Boat Building

    Germany begins large scale U-Boat building programme
    • Oct1939
  • 30,000 merchant seaman lost
    757 u-boats sunk or destroyed
  • 28,000 u-boat sailors lost
    5,000 cargo vessels sunk
  • 35,000 allied sailors lost
    6,000 RAF aircrew killed

ArchiveView all stories

Convoy sails to run U-boat gauntlet

A convoy of nearly four dozen merchant ships protected by nearly 20 Royal Navy warships has sailed for the New World – running the gauntlet of more than 100 U-boats. Convoy ONS5 – Outbound North (Slow) 5 – mustered off the west coast of Scotland yesterday as groups

of merchant ships from south Wales, Liverpool and Scotland joined forces. They are heading for ports in North and South America – most to pick up cargoes to bring back to the United Kingdom to support our war effort, some to deliver coal.

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Now and then

A nation dependent on the sea

Island Nation 1943

Serious losses of merchant ships put a strain on the Allied war effort. While the British population was never actually starved of food, nor her industries of raw materials, her armies of men, equipment or munitions - the shortage of shipping curtailed ambition and deterred the more offensive planning aspirations.

Island Nation 2013

With 95 per cent of the UK’s daily requirements still moving by sea and the future of resources and energy supply so dependent on the freedom to use the sea as a highway for trade, our prosperity as a nation is intricately linked to the sea and the role of the Royal Navy.

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HMS Duncan

Warship 1943

D-class destroyer HMS Duncan served with renown escorting convoys in the Mediterranean and West Africa. She joined the North Atlantic escort ships in May 1943, as the Senior Officer Escort for two key convoys ONS 5 and SC 130.

Warship 2013

The type 45 destroyer HMS Duncan, the sixth and final of the new sophisticated class of air defence destroyers, arrived at her home base of Portsmouth in March 2013.

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Date: 24th - 28th May
Liverpool was the national focus for the 70th anniversary commemorations and events

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Date: 9th - 13th May
Events held in London to mark the 70th anniversary

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Date: 10th - 12th May
Events held in Derry~Londonderry to mark the 70th anniversary

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Cargo Reports

'Imports into the United Kingdom', Table 161, in the Central Statistical Office, Statistical Digest of the War (London: HMSO, 1951) - Scale in 100's of Tonnes

Date Stocks thousands of tonnes Notes
Food Raw materials Total Oil
January 1941 10.94 12.77 5.41 U-boat menace grows
March 1941 9.15 12.02 8.42 Western Approaches Command formed in Liverpool
March 1941 11.23 12.77 9.53
April 1941 10.38 12.19 8.77
May 1941 13.31 13.69 11.86 Engima device captured by HMS Bulldog
June 1941 15.57 11.5 12.08 U-boat presence increases North and East Atlantic
July 1941 15.44 10.41 12.27
August 1941 13.6 12.78 14.16
September 1941 12.79 14.64 17.11
October 1941 12.39 16.32 14.65
November 1941 9.54 11 12.82
December 1941 13.2 12.79 12.59 USA enters the war
January 1942 9.84 9.6 10.37 U-Boats target shipping off US East coast
February 1942 9.56 8.66 11.39
March 1942 10.15 8.70 7.24 First sighting of U-boat using HF/DF
April 1942 10.99 9.5 8.96
May 1942 11.62 9.89 6.23 U-boats target trans-atlantic routes
June 1942 10.47 9.7 7.74 RAF target U-boats
July 1942 9.58 11.28 9.88 Convoy system reduces shipping losses
August 1942 6.74 11.8 9.16 U-boats return to North Atlantic
September 1942 8.82 11.89 10.75
October 1942 7.23 12.17 9.42 Operation Torch
November 1942 6.02 6.36 9.03 U-boat attacks intensify
December 1942 5.51 6.3 9.43
January 1943 5.31 5.98 8.57 RAF bomb U-boat bases
February 1943 6.33 5.51 8.95 North Atlantic air gap closed
March 1943 8.74 10.17 9.96 Heavy u-boat attacks increase
April 1943 11.73 10.2 10.71
May 1943 10.22 8.74 12.81 Black May: Battle reaches climax
June 1943 11.73 13.12 14.67 U-boats withdraw from North Atlantic
  • Food imports
  • Raw material imports
  • Oil imports

Crucial Convoy Air Cover

Flying from the pitching decks of escort carriers and hastily converted MAC ships (Merchant Aircraft Carriers), Royal Navy aircraft and their aircrews played a vital role in protecting the convoys and hunting U-Boats.

Captain 'Johnnie' Walker

If any individual could claim to have turned the tide against the U-boat, then it would be Captain 'Johnnie' Walker, a man who destroyed more U-boats than any other. Walker had spent much of the inter-war years specialising in anti-submarine warfare.