The 1958 Pakistani coup d'état refers to the events between October 7, when the President of Pakistan Iskander Mirza abrogated the Constitution of Pakistan and declared martial law, and October 27, when Mirza himself was deposed by Gen. Ayub Khan, the Commander-in-Chief of the Pakistani Army. Pakistan's first military coup followed a period of prolonged political instability in which Pakistan's dominant political party, the Pakistan Muslim League, was unable to successfully govern on the basis of shared programs or policies. Broadly, political scientists have argued that the susceptibility of a military system to coups is inversely correlated with the strength of its political parties.