Battle of the River Plate

Page 3 – The outbreak of war

New Zealand’s naval strategy ensured a worldwide perspective in 1939. War plans developed by the Admiralty called for one of New Zealand’s cruisers to join the Royal Navy’s America and West Indies Squadron, which guarded an area through which New Zealand trade passed. The other cruiser would remain in the South Pacific to guard shipping against enemy raiders.

As the international situation darkened in late August 1939, the likelihood of these plans being implemented suddenly became very real. Both New Zealand cruisers were hurriedly readied for sea. Ships’ bottoms were cleaned, supplies were loaded, and crews were brought up to their war complements. In HMS Achilles’ case, this amounted to 31 officers and 536 ratings, of whom five officers and 316 ratings were New Zealanders.

Early on 29 August, with Germany preparing to invade Poland, the Admiralty requested that the ships move to their war stations. Seven hours later Achilles put to sea, bound for Balboa in Panama’s Canal Zone. Soon afterwards HMS Leander was dispatched to Fanning Island with a 32-man detachment to guard the cable station there and prevent a raid such as the German East Asiatic Squadron had mounted at the outset of the First World War.

Achilles was well away from New Zealand when, shortly after midnight on 3 September, Captain Parry received a signal from London: ‘Commence hostilities against Germany.’ The previous day he had been ordered to head for the Chilean port of Valparaiso, where Achilles arrived on 12 September.

The Battle of the Atlantic

Of all the battles waged during the Second World War, arguably the most important was the Battle of the Atlantic, the struggle to keep open the sea routes to the British Isles. The outcome of this battle was vital to the survival of Britain and, later, to the eventual liberation of Europe by providing a staging point for the intervention of American power. This battle, fought by naval and air forces and the civilian seafarers of the Merchant Navy, began on the first day of the war and continued to the last.

At the outset, the battle also involved denying the Atlantic and other sea routes to Germany. An immediate task for the Royal Navy was to track down and destroy the estimated 237 German merchant ships at sea or in foreign ports. As well as cutting off German trade, this action would prevent these vessels being armed and used to prey on Allied trade.

For six weeks Achilles played its part in this worldwide effort, moving along the coasts of Chile, Peru, Ecuador and Colombia in order to deter German ship movements. The only Allied warship on this coast (all the South American countries were neutral), it was ready to intercept any German merchant ship heading for refuge in a neutral port or any of the 17 ships already holed up at various places that might dare to put to sea.

In time the Battle of the Atlantic became mainly a fight against German U-boats seeking to strangle British sea lines of communication. But at the outset there was also a significant danger from enemy surface vessels: armed merchant raiders and the German Navy's warships. In 1939 that navy was not strong enough to challenge British command of the seas as it had in the First World War, but it contained a number of powerful warships especially suited for commerce raiding. Among them was the 'pocket battleship' Admiral Graf Spee, capable of 28 knots and armed with six 11-inch (280-mm) guns in two triple turrets.

How to cite this page

'The outbreak of war', URL:, (Ministry for Culture and Heritage), updated 10-Jan-2022