The victory of the Persian Constitutional Revolution in Iran in 1906 marked the start of parliamentarism in Iran. The causes of the Constitutional Revolution could be summarized as follows:
In the 18th century, the Qajar dynasty's failure to administer state affairs came to the limelight in each and every domain. Defeats in rapid succession from Russia and loss of lots of land in northeast and northwest including Caucasus and parts of what is today known as Central Asia, the loss of Afghanistan due to Britain's intervention, giving colonial-style economic privileges to the Russian and British governments including the 1890 Concession of the Tobacco Regie in Persia were all indicative of the incapability of the former rulers running the country. In addition, governors’ acts of injustice against people in different parts of the country, nationwide poverty and insolvency, and the Qajar kings' unnecessary and costly trips to Europe showed the ruler's problems. Meantime, adoption of a firm stance by senior and influential clerics and religious scholars in Iran, and the Iraqi cities of Najaf and Samarra against the Qajar kings, particularly in the final days of power for Nasser ad-Din Shah, raised public awareness and mobilized people from different walks of life against the Qajar kings' injustice. This clerical movement came to fruition with the victory achieved in the Tobacco Movement. Furthermore, measures undertaken by Abbas Mirza and Chief Ministers like Mirza Abdol-Qassem Qaem and Amir-Kabir for modernism, sending students abroad to study, formation of a modern Army and establishment of printing house and technical school, constituted other factors that raised national awareness and persuaded people to join the Constitutional Revolution. Intellectuals like Akhundzadeh, Malkom Khan, and Mirza Aqa Khan Kermani, who set up secret associations and printed newspapers to promote progressive thoughts through articles were among other factors of the victory of the Constitutional Revolution.
Among the four aforesaid groups of factors, the role of the clergy and intellectuals in creating parliamentarism in Iran is justified. Despite differences between these two groups, they held a common view on one point, i.e. the necessity to curtail the monarchal power to enforce rule of law and parliamentarism in a bid to avert despotism. This common view and coordinated action triggered a historical event, known as the Constitutional Revolution. That opened a new chapter in the contemporary history of Iran, which was then known as Persia. The Constitutional Revolution hit some snags; however, its legacy has survived throughout years. It was the most important factor showing people's involvement in determining their own political fate. The legacy of the Constitutional Revolution is parliament which has been through ups and downs. In other words, the establishment of legislative body and separation of powers cleared the way for the first steps to be taken towards democracy in the country.
The Persian Constitutional Revolution recognized the National Consultative Assembly as the very foundation of Constitutionalism. The main task assigned to the National Assembly was to stabilize Constitutionalism in the country and strengthen the position of legislative power vis-à-vis executive power. Nonetheless, it must be taken into account that in then Persia parliament was not as influential as it was in some European countries. In Europe, the parliamentary procedure was born out of the society and had experienced balanced growth based on historical conditions and in consistency with requirements of each and every period. In Iran, parliament was an imported organ, which was supposed to replace the absolute power of the Shah. However, the performance of parliament in the final years of Qajar in power and throughout the Pahlavi regime proved that cultural and political grounds in Iran could not digest the fallout from marginalizing absolute monarchy and supplanting it with democratic organs.
In the wake of the victory in 1979 of the Islamic Revolution, this important objective was achieved to a favorable extent owing to the historical experience of the Qajar and Pahlavi dynasties.
In the aftermath of the 1979 Islamic Revolution, the political structure changed in Iran. The National Consultative Assembly was no exception. The official name of parliament was "National Consultative Assembly" in the Constitution of the Islamic Republic of Iran. On May 29, 1980, it was renamed the Islamic Consultative Assembly, but it remained unchanged in the Constitution. Finally, during the revision of the Constitution in 1989, the National Consultative Assembly was officially renamed the Islamic Consultative Assembly.
Unlike the pre-Revolution era, post-revolution parliament was powerful. In a public speech, Iran's late Supreme Leader Ayatollah Ruhollah Khomeini said that the parliament was at the top of state affairs. Therefore, MPs were the main decision-makers on political issues in the country. After the Islamic Revolution, the parliament was dubbed the House of the Nation. Of course, post-revolution parliaments have not enjoyed equal authority as in some terms of parliament influential MPs and political conditions in the country had given rise to a powerful and effective parliament. However at some points, due to political infighting and factionalism, the Assembly had seen its power decline in some terms.
The Guardian Council was a product of the first Constitution in Iran, but it had remained ineffective in practice. Under the Islamic Republic, it was revived and turned into one of the most significant organs of legislative power in Iran. The main task assigned to the Guardian Council on legislation is to make sure laws comply with Islam and the Constitution. There were always differences of view between parliament and the Guardian Council. Due to the significance of such differences, during the revision of the Constitution in 1989 under the order of Imam Khomeini, the Expediency Council was established as an advisory and arbitration body to advise the Supreme Leader and settle disputes between parliament and the Guardian Council.
This research has been drawn up in two general sections – first about the 24 terms of National Consultative Assembly and second about the 9 terms of Islamic Parliament of Iran. Each parliamentary term is studied independently. For each term, historical conditions, challenges, main incidents, the quality of elections, lineup, and number of MPs, lineup of Presiding Boards and their performance, legislative and political activities, concluding thoughts, the parliament's involvement in politics, important and outstanding activities at the national and international levels, political parties, and groups vying in the election and the most important pieces of legislation of each assembly have been reviewed. In the second section, diagrams and tables have been used for more clarification and details.