Seyyid Zia al-Din Tabatabai, who had orchestrated the coup d'etat in February 1921, was forced to resign from the prime ministership in only three months. Reza Khan, one of Zia's military collaborator in the coup, however, remained in the successive cabinets as the Ministerof War. After consolidating his political power steadily, he formed his own cabinet in October 1923. And finally he crowned himself as the founder of the Pahlavi dynasty in April 1926.
This paper examines the Iranian politics in 1921-1923 while in his office as the Minister of War regarded as the formative period of his dictatorship. In addition, the British policy towards Iran in those days is also considered. What factors allowed him to grasp such a dictatorial power is explored through these analyses.
In this sense, it should be firstly noteworthy that post-coup cabinets in Tehran consistently encountered with political and military threats in the provinces. Certainly, Gilan Republic and Colonel Taqi Khan's revolt in Khorasan against central authority were overthrown. But subsequent disorder caused by tribal assaults and plunders, especially in the north, enlarged the government dependency on the army, which became a main prop of Reza's political power. Therefore, he unified the armed forces and strove to ensure the military budget for the increasing troops, sometimes ultra vires.
On the other hand, the cabinets which alternated one after another could not prevent his arrogations, mainly because of the vulnerable leadership of the prime ministers and the Qajar monarch. Furthermore, the Majles (National Assembly), although it was harmonious in an anti-British attitude at the outset, began to split on factionalism, which not only brought the each cabinet to a crisis, but also weakened the sociopolitical movement against Reza's tyrannical behavior.
Also it is necessary to add special attention to the opinion of his opponents in the Assembly. Among them even Seyyid Hasan Moddares who criticised Reza most vehemently was also obliged to recognize his achievement as the Minister of War. This partly-affirmative appraisal can be commonly seen in the other political leaders. As a result, Reza was exempted from suffering a fatal blow in the power struggle.
Iranian historical scholars have frequently emphasized that the British support to the establishment of strong central government decisively helped his rise to dictatorial power. However, the role of the British in this period was extremely passive and at best among secondary factors. It may need to be comprehended in the context of the above-mentioned internal factors and their interaction.