I was briefly reading up the history of Muslim conquests and began to wonder how the entire process of spreading Islam was done exactly. We have all heard of “Islam was spread by the sword” but how accurate is that statement? Where and has this statement been borne from? (Orientalists?)

 I know during the Prophet’s time he (saw) sent out letters inviting people to accept Islam, but I had not realised there was a clause relating to this as it was commonly portrayed to be an open invitation with no compulsion to accept. The following is an excerpt of such a letter sent to Persia (Iran):

“In the name of God, the Beneficent, the Merciful. From Muhammad, the Messenger of God, to the great Kisra of Iran. Peace be upon him, who seeks truth and expresses belief in God and in His Prophet and testifies that there is no god but God and that He has no partner, and who believes that Muhammad is His servant and Prophet. Under the Command of God, I invite you to Him. He has sent me for the guidance of all people so that I may warn them all of His wrath and may present the unbelievers with an ultimatum. Embrace Islam so that you may remain safe. And if you refuse to accept Islam, you will be responsible for the sins of the Magi.”[8]

Source

Other sources speak of “accepting Islam or be subdued”

Now if Muslim conquests were indeed non-violent and were initially built on trade and export as is commonly proposed as the most effective and speedy method by which Islam spread, then on which occasions was it spread through battles and capturing other lands/cities/tribes/? I know vaugely of the Crusades, so I assume it to be the “norm” of past centuries and era’s to create empires and let their influence  and allow them the opportunity to attain “salvation” by reigning over foreign lands, peoples and cultures. Coloniasm isn’t any different. Some would say the same about globalisation.

When was it presumed to be necessary to let battle commence? Was it in refusal of the invitation letter? Direct or indirect misdealings and/or threat?

Books on this topic are usually incredibly biased (as are most historical books on any event) which is why whenever I have referred to it, it just confuses the issue further.