The Seerah of Rasoolullah (saw) speaks of this since the beginning of the Da’wah to Islam, and until the establishment of the State… and prior to establishing the State was the Prophet’s (saw) seeking of material support (Nussrah) from the people of power and protection who form the components of the State according to the reality of the region around them. For this reason, the Prophet (saw) went to the strong tribes calling them to Islam and seeking Nusrah from them as he (saw) did when he sought Nusrah from Thaqeef, Bani Amer, Bani Shayban, and the Ansar in Madinah, as for the small tribes, he used to merely call them to Islam… He continued doing this despite the difficulties and hardships he suffered, and the continuance of a matter in which there is hardship is the Shari’ indication that it is Fardh (an obligation) as in Usool…
Thus, the Messenger of Allah (saw) continued in seeking the Nusrah from the people of power and protection, as one tribe caused his feet to bleed, and another rejected him, while another tribe put forth conditions, however, and despite all that, he (saw) continued his work, steadfast upon what Allah (swt) revealed to him without changing this method to another method such as ordering the Sahabah to fight the people of Makkah, or fight some tribes to establish the State among them, and his Sahabah were heroes who feared none but Allah, but he (saw) did not order them to do so, but continued to seek Nusrah from the people of power and protection until Allah (swt) facilitated for him (saw) the Ansar. Thus they gave him the second pledge of Al-Áqabah, after Musáb (raa) succeeded in the mission assigned to him by the Messenger of Allah (saw) in Madinah, so in addition to Allah’s facilitation to him of men of the people of power to give him victory, he (raa) had made Islam, by the will of Allah, enter the homes of Madinah, and created in it a public opinion for Islam, thus, this public opinion embraced the pledge of the Ansar, allowing the Messenger of Allah (saw) to establish the State in Madinah through a pure and clear pledge of allegiance, and a warm welcome from the people of Madinah for the Prophet (saw).
This is the Shari’ method of establishing the State, and it should be followed by origin (asl), because the basis of actions is adhering to the Hukm Shari’ (Islamic rulings), so if a Muslim wanted to know how to pray, he studies the evidences relating to Prayer, and if he wanted to perform Jihad, he studies relating to Jihad, and if he wanted to establish the State, then he should study the evidences of establishing it through the actions of the Messenger of Allah (saw), and no other method of the Prophet (saw) for the establishment of the State was mentioned except the one outlined in his Seerah (saw). And it includes the Da’wah to the people of power and protection who constitute the components of a State as per the region surrounding them, calling them to Islam, seeking Nusrah from them, and their pledge of allegiance through consent and choice.