The Republic of Yemen: formed in 1990 with the merger of the Yemen Arab Republic (north) and the People's Democratic Republic of Yemen (south).
Population: An estimated 16 million, growing by 3.7 per cent a year.
Area: 536,869 sq km. Bordered by Saudi Arabia, Oman, the Red Sea and the Indian Ocean, its borders have been a source of trouble with its neighbours.
Political capital: Sanaa (427,000); economic capital: Aden (285,000).
Armed forces: Estimated to total 42,000, 25,000 of whom are conscripts, with 40,000 reserves.
Ancient history: Yemen is one of the oldest inhabited regions in the world, and tradition says the capital Sanaa was founded by Noah's son, Shem.
In the ancient world, Yemen was famed as the centre of the frankincense trade, and was the site of the Kingdom of Saba. The Old Testament describes the visit of the Queen of Sheba or Saba to King Solomon.
Known in the Graeco-Roman world as Arabia Felix, the area had important Jewish and Christian populations until the Persian governor converted to Islam in AD628.
Modern history: The two parts of Yemen were previously under foreign occupation. Turkey finally withdrew from the north after a second period of occupation in 1919, and Britain ended 128 years of rule in the south with its withdrawal from Aden in 1967.
Yemen has been plagued by revolutions, a civil war in North Yemen in the 1960s, border clashes in the 1970s, and political assassinations and riots.
A bitter separation that lasted for hundreds of years ended with the merger in 1990. However, the armed forces did not integrate, and in 1994 a two-month civil war was fought between southern separatist forces led by Vice-President Ali Salem al-Baidh and the government forces of President Ali Abdullah Saleh.
Economy: Yemen is one of the Arab world's poorest nations with per capita GDP of $280 a year. Inflation was 5 per cent at the end of 1997, and unemployment is about 35 per cent. A small oil producer, Yemen produces some 390,000 barrels per day, of which 190,000 come from the south. Up to 30 foreign oil companies are operating in the main oilfields.
Yemen's 1998 budget totalled 350.1 billion rials ($2.5 billion at the free market rate of about 140 rials to the dollar). It abolished the official exchange rate of 50 rials to the dollar in 1996. The forecast deficit was 14 billion rials ($100 million).