In the months after Pearl Harbor, fighting raged across the Pacific Ocean, as Allied forces sought to blunt Japan's advance.
Japan captured islands throughout the Central and South Pacific, including the Philippines, where on April 9, 1942, more than 20,000 Americans surrendered — part of the largest army under US command ever to do so — and then were forced into the brutal Bataan Death March.
By late spring, the Allies started to see success. On April 18, 1942, the Doolittle Tokyo Raiders mounted the first US strike on the Japanese mainland. In early May, US and Australian ships turned the Japanese back at the Battle of the Coral Sea — the first naval battle in which the ships involved were never in sight of each other.
During the first days of June 1942, another battle was just getting started in the far northern Pacific.
The Japanese, spooked by the Doolittle Raid, sent a force to occupy some of the frigid, windswept islands at the western end of the Aleutian Island chain, which extends more than 1,000 miles from the Alaskan mainland.
Adm. Isoroku Yamamoto, chief of the Japanese navy, saw the Aleutians and Midway as anchors of a defensive perimeter in the northern and central Pacific. Attacking the former, he believed, would draw weakened US naval forces out of Pearl Harbor. At that point, he would attack the latter. When US forces were redirected to Midway, he would destroy them.
Japan's Northern Area Fleet, which included two small aircraft carriers, left the Kuril Islands for the Aleutians in May. The Aleutians are swept by cold winds and frequently shrouded in dense fog. Many of the islands have craggy mountains and scant vegetation.
The Northern Area Fleet was small portion of Yamamoto's overall force, but it reduced the number of carriers Yamamoto had with him at Midway. That helped the US Navy, which was already aware of Japan's plans, give Yamamoto a devastating defeat from which the Japanese navy never recovered.
Less than a year later, radio intercepts revealed to US forces Yamamoto's plans to inspect Japanese bases in the Solomon Islands. On April 18, 1943, US fighter planes shot down the bomber transporting Yamamoto, killing the mastermind of the Pearl Harbor attack.
The US knew of the Japanese plans by May 21. Adm. Chester Nimitz, commander of the US Pacific Fleet, kept his carriers for Midway but sent one-third of his surface fleet to the Aleutians. The first days of June 1942 saw scattered contact between US and Japanese forces, including a Japanese raid on Dutch Harbor that did little damage.
Source: US Army
The Japanese launched another raid on Dutch Harbor the following day, killing 43 US personnel and destroying 11 US planes at the expense of 10 Japanese planes. US planes located the Japanese fleet but couldn't attack. Nimitz's surface ships did not engage during this period.
Source: US Army
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