Why did the Holy Prophet Muhammad (saw) conquer Mecca, if Islam is not to be spread by the sword?

The Meccans had broken the peace treaty, so the entry into Mecca was justified. Yet no one was converted by force: whoever did not want to become a Muslim remained free and safe.

Many Western history books present the entry into Mecca as an attack through which Islam was spread by force. What is usually missing is what came before. There was a peace treaty between the Muslims and the Meccans, and it was the Meccans who broke it. So the reason for the entry came from their side.

What matters is what happened after the entry. No one was forced to accept Islam. Whoever wanted to become a Muslim could say so. Whoever did not was free to keep his faith. He only had to keep away from the fighting, for example by staying in his house, and then he was safe. Faith remained a free choice, just as the second verse above requires.

Many Meccans accepted Islam at that time, and many others did not. Those who accepted it had often been convinced in their hearts for a long time. Until then they had not dared to say so openly, out of fear of the powerful leaders of Mecca. When that fear was gone, they spoke out what they had long believed.

The hadith above also shows how narrowly the permission to fight in Mecca was limited. It applied only for a short time, and afterwards the city was as sacred as before. No one may cite it as a reason to shed blood there.

The conquest of Mecca is therefore no proof that Islam was spread by the sword. Rather, it shows that even a victor, after years of persecution, forced his faith on no one.