Final answer:
The success of the Muslim conquests was due to the use of peaceful agreements offering religious freedom in exchange for taxes, military prowess coupled with vulnerabilities of opposing empires, and an inherent expansionist motive sustained by the spoils of war and effective military campaigns.
Step-by-step explanation:
The success of the muslim conquests, particularly during the seventh and eighth centuries, can be attributed to a combination of factors that played a critical role in the rapid and widespread expansion of the Islamic state. One significant reason was the strategic use of peaceful agreements with conquered cities and regions which often involved terms that allowed for the protection of residents, their belongings, and the right to practice their religion in exchange for paying taxes to the new Muslim government. This policy promoted relative stability and integration of new territories into the Islamic state.
Another key factor was the military prowess and tactics of the Arab-Muslim forces. The Arab-Muslims brought together experienced fighters who had adopted Roman and Persian military tactics, excelling in siegecraft, intelligence operations, and battlefield strategy. This capability was enhanced due to the vulnerabilities of the Byzantine and Sasanian empires, which had been weakened by long-term conflict that left them less able to resist the Arab-Muslim expansions.
Lastly, the inherent motives for expansion played a significant role. The early Islamic state held a strong desire to expand, driven by a sense of divine favor and possibly by the material wealth and resources available in the lands of the Sasanian Persia and Byzantium. The expansions were also sustained by the spoils of war, which were vital for maintaining the army of the caliphate. These conquests were characterized by mobile and effective military campaigns that made quick expansion possible.