Iran, where a presidential election will take place on Friday June 12, is one of the largest countries in the Middle East, a major oil producer and, since 1979, an Islamic republic.
Geography: With an area of 1,648,195 square kilometres (659,278 square miles), Iran is two-and-a-half times the size of the US state of Texas, and around seven times as big as Britain. Most of the country is a high plateau, and almost 20 per cent is desert.
Iran has land borders with Iraq, Turkey, Armenia, Azerbaijan, Turkmenistan, Afghanistan and Pakistan. It borders the Caspian Sea to the north and the Gulf, including the strategic Straits of Hormuz, to the south.
Population: 71 million, of whom around 50 percent are ethnic Persians, 20 percent Azeris and 10 percent Kurds. Other inhabitants include Turkmen, Arabs, Baluchis and Armenians.
Capital: Tehran. Other major cities are Mashhad, Isfahan, Tabriz and Shiraz.
Language: Persian (Farsi).
Religion: Around 99 percent Muslim, with small communities of Christians, Jews and Zoroastrians. The official faith is Shiite Islam, to which 90 percent of Iranians subscribe. Around nine percent of the population are Sunnis.
History: Iran is the modern descendant of the Persian empire, founded in 550 BC. Shiite Islam was declared the official religion in 1501. It came under Arab rule from the seventh century.
In the 19th century Iran became increasingly subject to great power rivalry, notably between Britain and Russia.
In 1921 Reza Khan staged a coup, and was crowned emperor in 1925. He was succeeded by his son Mohammad Reza Shah, who was backed by the United States but overthrown in 1979 by the Islamic revolution.
In 1980 neighbouring Iraq attacked Iran, and the ensuing war lasted eight years and left some one million people dead on both sides.
The US-led invasion of Iraq 2003 brought American troops to Iran's border, but strengthened the country's hand in other ways, as a Shiite-dominated government came to power in Baghdad.
In recent years the United States has accused Iran of destabilising Iraq, and also of seeking to gain nuclear weapons. Since 1980 Iran has had no diplomatic relations with Washington, which in 2002 labelled it as part of an "Axis of Evil" along with North Korea and Iraq.
Political Institutions: The constitution affirms the primacy of religious power, and gives ultimate authority to a supreme spiritual guide, currently Ayatollah Ali Khamenei.
President Mahmoud Ahmadinejad, elected in 2005, heads the government but has no control over key institutions such as the courts and the armed forces.
Economy: The economy is 80 per cent controlled by the state. The Iranian economy has been contracting since 2005 due to volatility in oil prices and UN sanctions, imposed in response to Iran's nuclear programme, which discourage foreign investors.
Iran is the world's fourth biggest producer of crude oil, which provides 80 per cent of the country's foreign exchange earnings. It is a member of the Organisation of Petroleum Exporting Countries.
Unemployment: 12.5 per cent.
Inflation: more than 25 per cent.
Armed Forces: Around 523,000 men (IISS, 2009)