Between 1964 and 1973, Afghanistan was a constitutional monarchy, for the first time in its history. The head of government was the prime minister, appointed by the king and responsible to the bicameral legislature. This system gave way to a more traditional authoritarian system on 17 July 1973, when Afghanistan became a republic, headed by Muhammad Daoud Khan, who became both president and prime minister. A new constitution in 1977 created a one-party state with a strong executive and a weak bicameral legislature. The communist PDPA abrogated this constitution after they seized power in April 1978.
Between 1978 and 1980, a communist-style 167-member Revolutionary Council exercised legislative powers. The chief of state (president) headed the presidium of that council, to which the 20-member cabinet was formally responsible. A provisional constitution, introduced in April 1980, guaranteed respect for Islam and national traditions, condemned colonialism, imperialism, Zionism, and fascism, and proclaimed the PDPA as "the guiding and mobilizing force of society and state." Seven years later, a new constitution providing for a very strong presidency was introduced as part of the PDPA's propaganda campaign of "national reconciliation." Najibullah remained as president until April 1992 when he sought refuge at the UN office in Kabul as mujahidin forces closed in on the city.
With the fall of the Najibullah government a Seven Party Alliance (SPA) of the Islamic groups announced plans to set up an Interim Afghan Government (AIG) charged with preparing the way for elections. However, Professor Burhanuddin Rabbani coopted the process by forming a leadership council that elected him president. Subsequent fighting among warring factions plunged the country into anarchy and set the stage for the emergence of the ultra-conservative Islamic movement, Taliban, which ousted the Rabbani government and as of mid-2000 controlled all but the northern most provinces of the country. No new constitution was drafted since the end of the Najibullah government.
The Taliban, led by Mullah Mohammed Omar, formed a six-member ruling council in Kabul which ruled by edict. Ultimate authority for Taliban rule rested in the Taliban's inner Shura (Assembly), located in the southern city of Kandahar, and in Mullah Omar.
With the fall of the Taliban in December 2001, an interim government was created under the leadership of Hamid Karzai by an agreement held in Bonn, Germany. He was elected head of state in June 2002 of the "Islamic Transitional Government of Afghanistan (ITGA)," by the Loya Jirga convened that month. He named an executive cabinet, dividing key ministries between ethnic Tajiks and Pashtuns. He also appointed three deputy presidents and a chief justice to the country's highest court. Elections for a new government were scheduled for 2003.