Iran is a theocratic Islamic republic governed under the constitution of 1979, which codified Islamic principles of government. The constitution was revised in 1989, expanding presidential powers and eliminating the position of prime minister. The president, who is popularly elected for a four-year term, serves as the head of government. The supreme leader, who effectively serves as the chief of state, is appointed for life by an Islamic religious advisory board (the Guardian Council) that works in close conjunction with the government. The legislative branch consists of the 270-seat Islamic consultative assembly, or parliament, whose members are elected by popular vote. Although Iran has no legal political parties, there are at least three important political groups, as well as a number of pressure groups, some of which have been suppressed by the government.
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Iran's government is defined as a theocratic republic. A theocracy is ruled by religious leaders who are believed to be acting on behalf of their deity. A republic is run by a democratically elected leader. In Iran, the government is run by an elected president, parliament, local councils and an "Assembly of Experts"- all of which must follow Islamic principles.
Because of its theocratic elements, Iran is typically considered an Illiberal Democracy (as opposed to Liberal Democracies like the United States, France, Germany, et al.). That is to say that while there are certain trappings of democracy, they are not sufficient to create a truly democratic atmosphere. Several things that Iran has which make it a democracy include: regular voting periods, different candidates, and different parties with conflicting interests. Several things that Iran has, which preclude it from being a Liberal Democracy include: suppression of political expression, unelected leadership (in the form of the Supreme Leader and his council), repression of political parties, widespread voting fraud, restrictions on the freedom of speech and in the press, required loyalty oaths (this prevents members of Parliament from speaking out on issues for minority constituencies which have been harassed by the government), and unbalanced campaigning (where the "desirable" candidate can slander other candidates, but cannot himself be publicly slandered to the same extent).
oligarchy
Monarchy
Islam is mostly in iran now
`Not very stable
Parlimentary democracy
Yes
The most important form of leadership on Iran is the Islamic hierarchy that has the final say over government activities. The top religious ruler in Iran has the title of Ayatollah.
Form practiced in Mycenae (1450 B.C.)
Iran had a monarchy before 1900. Qajar monarchy.
Mohammad Reza Shah Pahlavi was the Shah of Iran from 1941-79. He was deposed by the Islamic Revolution in 1979. After the Islamic Revolution, Iran changed its form of government to an Islamic Republic, and control was given to the leader of the Revolution: Ayatollah Khomeini. This new form of government is the form of government in present-day Iran, as well.
parliamentary democracy
Afghanistan, Saudi Arabia, Iran, Pakistan etc