A few months later, public pressure forced Vosough out of office, and Moshir al-Doleh became Prime Minister. The new Premier invited Dr. Mossadegh to join the cabinet as Minister of Justice.

In his return to Iran from the Persian Gulf, due to the request of the people of Shiraz, he accepted the governorship of the Fars province until the coup d'etat of 1921. There, too, he took effective steps towards the security of the people.

When the British backed coup of Seyed Zia and Reza Khan took place in 1921, Mossadegh was one of the few Iranian politicians who questioned the legitimacy of the coup government, and resigned his post as the governor of Fars.  After his abdication, on his way to Tehran, the Bakhtiari tribe invited Mossadegh to be their guest. He lived there until the Zia government collapsed after 100 days.

After Zia's fall, Ghavam al-Saltaneh became the new Premier and Dr. Mossadegh was posted as the Finance Minister with special authority.

After the fall of Ghavam's government, and Moshir becoming the premier once again, Mossadegh was invited to become the governor of the Azerbaijan province. He accepted the post provided that full authority over the province's armed forces is given to him. At the end ,however, due to the provincial army commander's disobedience, who got his orders from Reza Khan (the War Minister), Mossadegh resigned and returned to Tehran.

In May 1923, Mossadegh became the Foreign Minister of Moshir's cabinet, and strongly opposed the British  government demanding  2 million Pounds from Iran, for the creation of the Iranian southern police (which protected Britain's interests!.)

After Moshir's resignation, Reza Khan (Commander of the Armed Forces), took office as Prime Minister. 

After the occupation of Iran by the British and Russian armies in 1941, Reza Shah was ousted and exiled to South Africa where he died a couple of years later.

In the elections of the 14th Majlis (Parliament), Dr. Mossadegh was surprisingly honored by the nation and elected as the first deputy from the Capital.

In the 15th Majlis elections, because of the election rigging, Mossadegh did not get the chance to enter the Parliament, so the British could lobby the passage of the 1933 oil agreement signed by the ex-Shah, with the new cabinet, and, therefore, plunder the Iranian oil for another 60 years. With the public pressure mounting, the wish of the British government could not come true, and the term of the 15th Majlis ended. But the Shah, at the request of the British, formed a Constituent Assembly, and extended his powers as a constitutional monarch. It was also during this period that, Mossadegh and his companions formed the Jebhe Melli (National Front) of Iran, which played a great role in nationalizing the Iranian oil industry.

Despite all the interference and frauds of the Shah during the 16th Majlis elections, the fake ballot boxes were announced expired, and the Royal Court minister was assassinated. In the second round of the elections, Mossadegh and a group of his companions were elected. It was this Parliament that approved the nationalization of the Iranian oil industry. A while later, the Majlis elected Mossadegh as the new Prime Minister.

When Mossadegh became Premier in 1951, the first thing he did after introducing his cabinet, was the enforcement of the Oil Nationalization Bill.

Following the British law suit against Iran and taking it up in the United Nations Security Council, Dr. Mossadegh traveled to New York  to defend Iran's rights. Then he went to the Netherlands to defend Iran at the Hague, which voted in favor of Iran in its huge international legal encounter with England. On his way back home, Mossadegh also paid a visit to Egypt where he was magnificently welcomed.

Dr. Mossadegh and His Supporters in Front of the Majlis

In March of 1953, the Royal Court decided to carry out a conspiracy against Dr. Mossadegh. On the first day of March, it was plotted, the Shah would leave for Europe pretending that Mossadegh forced him to do so. On the other hand, some hooligans and expelled army officers would gather in front of the Royal Palace to prevent the Shah's departure and attack and kill Mossadegh when he was coming out of there. The plan fell flat when Mossadegh was informed in advance and escaped the scene unharmed.

General Afshar-Toos, the loyal police chief of Mossadegh's government, was brutally murdered by the Royal Court's agents and the expelled officers.

Disputes between the Parliament and the cabinet increased, and following the Majlis member's abstractions Mossadegh declared a national referendum to let the people choose between dissolving of the Parliament, or cabinet's resignation. In this plebiscite,( criticized by many, because of the separation of the Yes and No ballot boxes, and not being held at the same time nationwide), the majority voted against Majlis. In August 1953, therefore, the Parliament was officially dissolved.

On August 16, 1953, in an American-British orchestrated conspiracy, the Shah dismissed  Dr. Mossadegh. The chief of the Royal Guards served  Mossadegh with the formal dismissal notice. He was also ordered to occupy the house by the Royal troops as he was ordered to. But when soldiers reached the Mossadegh's house, Mossadegh's guards immediately arrested the Royal Guard's chief and his troops. The coup was publicized and the Shah fled to Italy.

On 17th and 18th of August, people took to the streets in support of Mossadegh and the statues of the Shah and his father pulled down all over the country.

On August 19th, the secret services of the U.S and Britain (CIA - MI6), engineered a more precise and expensive coup  and this time succeeded in overthrowing Mossadegh's government. On this  tragic day, after bribing some people from different walks of life, those behind the coup managed to pull a large number of hooligans into the streets to rally against the national government of Dr. Mossadegh. Because of the police chief treachery, the mob reached the Prime Minister's residence and after hours of bombarding it and fighting a bloody battle with the small group of Mossadegh's loyal guards, they entered the house and after plundering it, they burned it down. Mossadegh and his companions used a ladder  to escape and took refuge inside the neighbor's house. Some of Mossadegh's previous companions were among the coup plotters.

During his trial in a military court, Dr. Mossadegh disclosed the secrets of the two coups against his government. He was sentenced to three years imprisonment after which he, now 74, was transferred to his country house in Ahmad Abad, and lived there under house arrest until his death. On March 4, 1967, Dr. Mossadegh died of cancer at the age of 84. His body was buried in one of the rooms of his residence. He was survived by 2 sons and 3 daughters.