The Japanese operations in the Indian Ocean were conceived after Pearl Harbor . After the attack on Pearl Harbor on 3 Dec 1941, the American Pacific fleet except for the aircraft carriers had been decimated. The carrier task force had returned to Japan for a refit and some much needed rest. However the war council thought it a fit time to operate against the British in SE Asia.
The Aim of the Imperial Navy
One aspect of World War II history that is not given much importance is the Japanese operations in the Indian Ocean. After the attack on Pearl Harbor on 3 Dec 1941, the American Pacific fleet except for the aircraft carriers had been decimated. The carrier task force had returned to Japan for a refit and some much needed rest. However the war council thought it a fit time to operate against the British in SE Asia. It was felt that limits of Japanese sea power should be as far as Ceylon, to facilitate an occupation of Burma.
Japanese Move in the Indian Ocean
Accordingly the commander of the carrier task force at Pearl Harbor, Admiral Chuichi Naguma was again appointed commander of the carrier force and was tasked with making the Japanese presence felt in the Indian Ocean up to the island of Ceylon.
Vice Admiral Chuichi Naguma
A word about Chuichi Naguma will not be out of place here. He had joined the Imperial navy in 1908 and was a graduate of the Naval War College. In 1925-26 he had visited the USA and UK to study first hand the tactics of the western navies. Though Naguma was an old time officer, who had basically served on surface ships, yet he understood the concept of air power and its integration with naval operations.
Composition of the Imperial Fleet
The Imperial navy flotilla given to Naguma for hisIndian Oceanoperations consisted of 41 warships including 19 destroyers, 7 cruisers, 4 battleships and more important 6 aircraft carriers. This was indeed a formidable task force and Naguma promised the war council and the Prime Minister, General Hideki Tojo that he would decimate the British fleet. Admiral Yamamoto also backed Naguma and plans for the operation were cast.
Japanese Armada Sails
The Japanese Armada sailed from the Celebes (a part ofIndonesia) on 26 March 1942. They leftStaringBay(Kendra) at dawn. Staring Bay and theportofKendrahad been captured by the Japanese in January 1942. Staring bay was an excellent anchorage which was a natural harbor as well.
Battles in the Bay of Bengal
The armada after entering the Bay of Bengal was split and one force commanded by Admiral Ozawa with one carrier and 6 destroyers headed deeper into the Bay of Bengal. In a swift operation this fleet sank 23 British ships and the Andaman Islands were threatened. The Main force under Naguma sailed towards Ceylon.
Domination over Ceylon
The British had received intelligence reports that the Japanese armada was approachingCeylon, but they were unable to establish its motives. They assumed it was prelude to an invasion ofCeylon, but now we know that Japanese had no plans at that stage to conquerCeylon. The commander of the British eastern fleet was Admiral Sir James Somerville. He had under him a force which was inferior in quality to the Japanese armada, but in numbers he had over 70 war ships. But he had only 3 aircraft carriers and thus was greatly handicapped.
The Japanese fleet reached the vicinity of Lanka by 31 March 1942 and Naguma put his plan into operation. An initial attack was mounted by aircraft from the carriers on Galle. The British were taken completely by surprise and the Japanese naval aircraft had a field day. The Japanese followed up by attacking the naval base at Colombo on 5 April 1942.
The attack was a great success and 3 warships and 27 aircraft were sunk and destroyed. The Japanese also carried out air surveillance and discovered two heavy cruisers on the high seas of the coast of Colombo. Both warships were attacked and sunk with over 400 sailors going down with their ships. The Japanese soon dominated the entire coast of Colombo and the result was that some of the British ships retreated to east Africa.
The Japanese now struck the naval base at Trincomalee about 113 km from Jaffna on the east coast on 9 April 1942. The British aircraft carrier Hermes was sunk. It received over 40 hits from the carrier borne aircraft and over 300 sailors lost their lives. Over all the Imperial Navy took complete command of the sea around Ceylon. In case Naguma had sufficient number of marines on board he would have captured Ceylon, but at that time it was not the Japanese aim.
By 10 April, Naguma was called back to Japan as Yamomoto had planned the engage the US fleet at Midway. But the Japanese operations in the Indian Ocean once again highlighted the potency of air power. Admiral Naguma committed suicide towards the end of the war in the battle of Saipan. Thus ended the career of a man, who was one of the foremost Japanese admirals during the Second World War.
In hind sight the operations in the Indian Ocean and attacks on Ceylon served no strategic purpose and were devoid of any planning or appreciation of the battle situation.