1. The River Plate December 13-17, 1939
Strategic Context
When World War II breaks out in 1939, the German Navy (Kriegsmarine) under Admiral Raeder is unprepared for global war. While the Adolph Hitler-approved Z-Plan calls for a 200-warship balanced fleet by 1948, at war’s outbreak it can muster only 74 major warships against Britain’s 275 and France’s 106. With the defeat of Poland, the bulk of the Kriegsmarine is concentrated in the North and Baltic Seas protecting Germany’s coast and sea communications as Hitler plans his attack on France in spring This leaves only U-boats and a few pocket battleships for the disruption and destruction of vital Allied merchant shipping in the Atlantic Ocean. Hans Langsdorff’s pocket battleship Graf Spee cruises the South Atlantic Ocean for two months, capturing or sinking nine ships as far as the Indian Ocean. The Royal Navy commits eight surface groups to hunt for Graf Spee, way out of proportion to the tonnage lost. After some intelligent guesswork, British Royal Navy Commodore Henry Harwood, leading a small cruiser force, stumbles upon Graf Spee north of the Falklands Islands near the River Plate.
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Stakes
+ A German victory would allow the Graf Spee to continue raiding British shipping and draw more warships to destroy her.
+ A British victory would end the Graf Spee’s threat to its shipping and free up warships to hunting other German surface raiders.
By Jonathan Webb, 2009

2. The River Plate, 1939 Strength
Kriegsmarine
16,200 tonnes
Well
Royal Navy
29,280 tonnes
Well
Hans Langsdorff
Henry Harwood
1 pocket battleship
1 armoured cruiser
2 light cruisers
By Jonathan Webb, 2009

3. South Atlantic c. 1939

4. Kriegsmarine Royal Navy
The battlefield consists of a small area of the South Atlantic Ocean. This area is east of the River Plate Estuary, which is between neutral Uruguay and Argentina (actually further than it appears on the map). Weather on this morning is described as good, clear, slight breeze, no clouds with extreme visibility, and a calm sea state with only a slight breeze from southeast.
Kriegsmarine
(Langsdorff)
URUGUAY
Montevideo
River Plate Estuary
ARGENTINA
South Atlantic Ocean
Royal Navy
(Harwood)

5. Royal Navy Kriegsmarine
Graf Spee
(Hans Langsdorff)
Type: pocket battleship
Launched: 1934
Displacement: 16,200 tons (full load)
Speed: 24 knots
Main armament:
6 x 11-inch guns
8 x 5.9-inch guns
Protection:
Main belt: 4 inches
Deck: inches
Turrets: inches
Under international law, the Graf Spee is only permitted to stay in a neutral port for three days which the Uruguayan authorities resolve to enforce. Harwood prefers Graf Spee stay in port until reinforcements can arrive to handle the powerful ship and so British diplomats protest; this way it appears they are anxious for Graf Spee to set sail as if there is an armada waiting for her. British diplomats reinforce this myth by spreading rumours that this armada is already stationed outside the harbour. In reality, only the heavy cruiser Cumberland arrives.
Langsdorff radios Berlin but only receives the typical order that he not allow his ship to be captured. Langsdorff decides to scuttle Graf Spee, which he orders to take place after burying the dead and releasing the prisoners. In a hotel, Langsdorff writes a letter to his family, lays upon the battle ensign of Graf Spee and shoots himself.
Harwood and Langsdorff exchange vicious salvoes, each landing respectable hits. Harwood realizes his position cannot last; Ajax has lost a turret, his ships seem to be firing “marshmallows” at the heavily armoured pocket battleship, and ammo is running low. Before his ships can make smoke and escape, Graf Spee also turns to retreat. Langsdorff is apparently disoriented after being knocked unconscious momentarily from a blast. Harwood orders his cruisers to cautiously shadow Graf Spee outside her guns’ range. The pursuit ends at the neutral port of Montevideo.
Graf Spee continues to smash Exeter until Ajax and Achilles charge Graf Spee to divide her fire. Exeter lands a glancing but direct hit on Graf Spee’s bridge before listing away at low speed with few functional weapons. Graf Spee begins to focus her guns towards Ajax and Achilles, which are already firing intently with all guns.
Exeter heads straight for Graf Spee while Ajax and Achilles steam ahead to cross her bow. This maneuver proves nearly fatal for Exeter as Graf Spee fires salvoes before Exeter can, and even when she does, the exchange is still lop-sided. Exeter is pummeled by the Graf Spee while landing few hits of her own. Meanwhile, Ajax and Achilles have yet to engage in combat.
Langsdorff spots Harwood’s cruisers steaming towards him at Langsdorff’s Graf Spee boasts thicker armour and heavier guns with more range, but is significantly slower. Harwood on the other hand questions whether any of his cruisers’ guns can sink Graf Spee and therefore must rely on their maneuverability. Harwood plans to divide Graf Spee’s fire by attacking in two separate divisions: the armoured cruiser Exeter in one group and the light cruisers Achilles and Ajax in the other. Click on units for more information about that particular ship.
Ajax
(Charles Woodhouse)
Type: light cruiser
Launched: 1933
Displacement: 9,280 tons (full load)
Speed: 32 knots
Main armament:
8 x 6-inch guns
8 x 4-inch guns
Protection:
Main belt: 2-4 inches
Deck: 2 inches
Turrets: 1 inch
Kriegsmarine
(Langsdorff)
Landmarks
URUGUAY
Montevideo
River Plate Estuary
ARGENTINA
South Atlantic Ocean
Cumberland
(Walter Fallowfield)
Type: heavy cruiser
Launched: 1928
Displacement: 13,400 tons (full load)
Speed: 32 knots
Main armament:
8 x 8-inch guns
4 x 4-inch guns
Protection:
Main belt: inches
Deck: inches
Turrets: 1 inch
Royal Navy
(Henry Harwood)
1 heavy cruiser
2 light cruisers
Kriegsmarine
(Hans Langsdorff)
1 pocket battleship
Royal Navy
(Harwood)
Achilles
(Edward Parry)
Type: light cruiser
Launched: 1931
Displacement: 9,000 tons (full load)
Speed: 32 knots
Main armament:
8 x 6-inch guns
4 x 4-inch guns
Protection:
Main belt: 2-4 inches
Deck: 2 inches
Turrets: 1 inch
Exeter
(Frederick Bell)
Type: armoured cruiser
Launched: 1929
Displacement: 11,000 tons (full load)
Speed: 32 knots
Main armament:
6 x 8-inch guns
4 x 4-inch guns
Protection:
Main belt: 2-3 inches
Deck: 2 inches
Turrets: inches
Ajax
(Charles Woodhouse)
Type: light cruiser
Launched: 1933
Displacement: 9,280 tons (full load)
Speed: 32 knots
Main armament:
8 x 6-inch guns
8 x 4-inch guns
Protection:
Main belt: 2-4 inches
Deck: 2 inches
Turrets: 1 inch

6. The River Plate, 1939 Casualties & Aftermath
Kriegsmarine:
Royal Navy:
1 pocket battleship (scuttled)
96 sailors or
100%
1 heavy cruiser (heavily damaged)
100 sailors or
33%
The loss of Graf Spee left only two other pocket battleships for surface raiding: the Lützow and Scheer. Although a number of German U-boat still operated in the waters, the South Atlantic became safer for Allied merchant shipping. The Battle of the Atlantic and Britain’s survival had only just begun.
By Jonathan Webb, 2009

7. The Art of Battle: Animated Battle Maps
By Jonathan Webb, 2009