life:

The Aleutian Islands are a chain of high mountains rising our of the North Pacific between Alaska and Siberia. There, among fog and sudden storms, the world is still in the making. Volcanoes blow rings of steam. Islets pop out of the water and then mysteriously vanish again. Earthquakes make and unmake harbors, cliffs, beaches and caves.

The shortest route between the U.S. and Japan lies through Alaska and out the Aleutians. From Attu to Tokyo is only1,750 miles…. Whoever controls the Aleutians has a flanking position on the whole ocean. [In June 1942 Japan] seized Attu and Kiska and remained a constant threat to Alaska, Canada and the U.S. until August 1943 when they were finally driven off. To defend the Aleutians against another attack, thousands of Americans are still stationed there.

Of all the U.S. outposts the Aleutians are probably the wildest and most inhospitable. There are almost no trees on the islands. There are few animals. The temperature seldom drops below freezing in winter or goes above 60 degrees in summer. There are as many as 250 rainy days a year and as few as eight clear days.

These days, the story of the Aleutian Islands Campaign was gradually forgotten by those who did not fight or serve there, or by those families that did not lose a loved one there.

Here, 70 years after Japanese forces seized control of Attu and Kiska islands early in the war, LIFE.com presents rare photos — most of which never ran in LIFE magazine — by Dmitri Kessel chronicling the day-to-day existence of Allied troops serving in the dramatic and forbidding landscape of the Aleutians.