Leaderboard

That’s an interesting question. Looking at the conquest by the Spanish conquistadors in the 16th century AD of the Western Hemisphere might shed some insights. The Spanish had a much smaller force that was equipped with modern weaponry. They faced vastly numerically superior forces that used premodern weaponry made of wood, stone, copper, and bronze. The indigenous tribes were stunned by the presence of horses, steel armor, swords, cannons, guns, and crossbows. The Arabs didn’t have these technological military advantages over their foes. The Arabs frequently didn’t suffer from such numerical disadvantages, either. The Spanish brought new diseases (especially smallpox) that worse-than-decimated the indigenous peoples they conquered. This made the vulnerable and weakened indigenous people more easily subjected. Disease may have played a role in the Arab conquest. The sources are unclear but the Arabs may have benefitted from the Plague of Justinian. The Spanish were able to recruit local tribes to fight with them. This was especially important for the Spanish conquest of the Aztecs who were loathed and feared by the surrounding tribes. This factor was, in fact, important in the Arab conquest of their enemies, including the Sassanians, Byzantines, as well as the Visigoths. The Arabs, for example, were able to elicit support from aggrieved Christian minorities against the Byzantines. The Arabs also had the advantage of facing Byzantine and Sassanian Empires that had weakened each other after decades of bloody fighting, leaving these Empires both economically and militarily exhausted. Like the Spanish, the Arabs were an impassioned and organized military force energized by an ideology. Most importantly, however, they both were able to exploit vulnerabilities in their enemies. Early Muslim conquests - Wikipedia This looks like a good book on the topic: