The first steps were taken to seize Siam (Thailand), Guam, Wake, Hong Kong, Malaya and the Philippine Islands. In Malaya they worked their way down each side of the peninsula, turning line after line of defence by moving inland along side-tracks, often on bicycle. Lightly equipped for jungle warfare, the Japanese soldier could live for days on a few rice balls carried in a hollow bamboo cane.

When the British battleship Prince of Wales and the battle cruiser Repulse tried to stop the Japanese landings in Malaya without air cover, torpedo aircraft sank them.

Singapore, with the largest British naval base in the Far East, was captured in February 1942, a catastrophe for the British imperial image.

General MacArthur defended the Philippine Islands, a US possession, for three months on the Bataan Peninsula with a small force led. When his troops, weakened by hunger and disease, were finally defeated the survivors were forced to make the so-called 'Death March' without food and water to a prison camp 100 km away, and were brutally clubbed and beaten by their Japanese overseers. MacArthur, who escaped, promised to return to free the Philippines.

The Japanese made three main drives through the Dutch East Indies. They crushed the weak defences of Borneo, Celebes, Sumatra and converged on Java, where in the Battle of the Java Sea, they destroyed an allied fleet of five cruisers in February 1942. Darwin in Australia was wrecked by a Japanese air strike from the powerful Nagumo Force.

The Japanese from Siam invaded Burma, a British possession. The Chinese sent help, hoping to keep the Burma Road open for supplies from the USA through Rangoon. But the Japanese soon overran the whole country and seemed on the point of invading British India.

The Nagumo Force of five heavy aircraft carriers and four fast battleships entered the Indian Ocean and bombed the British naval base of Trincomalee in Ceylon (now Sri Lanka). Fortunately for the British the fleet was away at sea and withdrew to East Africa.

The Japanese achieved their objectives, in half the time expected with the loss of nothing larger than a destroyer. But, knowing they had not wiped out the whole US Pacific Fleet at Pearl Harbour, they feared the Allies would strike back from Australia. The Japanese decided to cut the long supply line from the USA to Australia by moves towards the Fiji Islands, and to attack Midway Island and hope to lure the remnant of the US fleet into battle and destroy it. This plan led to the great Battles of the Coral Sea and Midway Island.