South Yemen's 2.2 million inhabitants, the vast majority of them Sunni Moslems, live in a hot, arid country the size of Nevada.

The country, officially the People's Democratic Republic of Yemen, won its independence in 1967 after 128 years of British rule and quickly established itself as a Marxist state.

In October 1979, South Yemen signed a 20-year treaty of friendship with the Soviet Union and in 1981 a trilateral treaty of friendship and cooperation with Libya and Ethiopia.

The capital, Aden, has been a major port for 2,000 years, and its location near the Horn of Africa, the Indian Ocean and the mouth of the Red Sea provides the Soviet Union with a strategic foothold on the Arabian Peninsula.

There are estimated to be up to 1,000 Soviet military personnel stationed in South Yemen, as well as from 300 to 700 Cubans and about 100 East Germans.

There have been unconfirmed reports that the Soviets have installed surface-to-air missiles in South Yemen and were building submarine facilities at their naval base on the Indian Ocean island of Socotra.

South Yemen's relations with its Arab neighbors have been stormy.

South Yemeni troops crossed into North Yemen (Yemen Arab Republic) in 1979 to join insurgents battling the government. The Arab League mediated a cease-fire, and South Yemen withdrew its troops less than a month after the fighting began.

More recently, North and South Yemen have held talks aimed at unifying the two countries. Border clashes with Saudi Arabia were reported in 1983 and 1984.