Five hundred years later, a religion with war and forced conversion as its heart burst out of the Arabian peninsula and pushed Christian Europe to the brink of collapse. That was Islam (the name means "submit !" in Arabic / Muslim is just the Arabic word derived from the same root meaning "he who submits"). The only significant periods when Christianity was forced on people with the edge of a sword were during the Crusades that occurred several hundred years after the Islamic conquest, conversion of Jews and muslims during the Spanish Reconquista (see Queen Isabel and King Ferdinand) and the forced conversion of native peoples in North and South America by the Spanish. If anything, more Christians were killed by other Christians during the wars between Catholics and Protestants than any pagans, muslims, etc. during the religion's two thousand year history.
Islam, on the other hand, has never made any pretense of "peaceful" conversion. The most tolerant of their lot were the Ottomans. But even in their case, the constant need for slaves not born as muslims to serve the sultan as soldiers, government workers, concubines, etc. required thousands of young Christians to be taken from their villages, circumcised, and converted to Islam by force (the system of "Devshirme") every year for the several hundred year history of that empire.
Next time you feel the need to compare Islam's bloody history to Christianity, try and get your facts straight. A lot of blood has been spilled in the name of both religions, but in one case the bloodshed is anathema to the philosophy of the faith. In the other, forcing people to convert with a knife at their throat is the norm and is specifically supported by parts of their scripture.