100 years ago today, December 12, 1925 (October 27, 1925 in the lunar calendar), the Pahlavi Dynasty in Iran was established. On December 12, 1925, the Iranian Constitutional Convention announced the establishment of the Pahlavi Dynasty. The Pahlavi Dynasty began with the coronation of Reza ShahPahlavi in 1925, and finally ended in the Islamic Revolution of Iran in 1979, when Iran's traditional monarchy collapsed. In February 1921, Reza Khan, commander of the Iranian Cossack forces, cooperated with pro-British politician Said Ziyadin to launch a military coup, establishing a new government with Ziyadin as prime minister and Reza Khan holding military power, temporarily retaining the Kazar Dynasty. Reza Khan tried his best to dominate military power. After becoming Minister of Defense in July 1921, he dismissed the British officers in the Cossack Division and placed them under absolute personal control. In September of the same year, the South Persian Rifles were disbanded as a British-controlled unit. In January 1922, an order was issued to unify the entire army, forcing the government to spend most of its revenue on military expenditures. Reza Khan brutally suppressed the revolutionary movement and extinguished the people's struggle in the Jilang region and Azerbaijan province at the end of 1921 and early 1922. In October 1924, Reza Khan suppressed the rebellion of the reactionary feudal aristocrats in Kuzestan and wiped out divisions in various places. Reza Khan and Prime Minister Ziyadin fought openly and secretly. After Reza Khan failed to attempt to reshuffle the cabinet in 1923, he publicly expressed his support for political reform. In 1924, he launched a Republican Movement, using the banner of abolishing the Khazar Dynasty and establishing a republic. Due to religious pressure, the Republican Movement was abandoned on March 31 of the same year and was supported by the Islamic elite. On October 31, 1925, Congress decided to depose the Khazar Dynasty and convene a Constitutional Convention to determine the form of future government. On December 12 of the same year, the Constitutional Convention announced the establishment of the Pahlavi Dynasty.