No, it was spread through persecution. In Bosnia, for example, the persecution historically came from Roman Catholics. The most infamous example of the first conversion, from paganism, took place in the city that is now known as Livno. In that massacre, more than 2,000 Bosnians were slaughtered and less than 300 survivors were converted. Records celebrating this great achievement and rewards presented to the missionaries who carried it out are still stored at the National Museum of Bosnia and Herzegovina and at the Vatican.
Once a significant number of Bosnians had been converted to Roman Catholicism, but their pagan families and friends were still being slaughtered, the Roman Catholic Church in Bosnia collapsed. The Bosnian Church developed, which held vaguely Bogumil beliefs and this Church was declared heretical by the Roman Catholic Church. This is when the persecution truly began in earnest. At several points (1094, most notably), more than 50% of the population of Bosnia and Herzegovina was exterminated by forces sent by Rome.
Persecution later came at the hands of Orthodox Christians, most notably Saint Sava who was Sainted in part for his campaign against the Bosnian Church and Roman Catholics. His forces along slaughtered many Bosnians - mainly in Srebrenica, Zepa, and the city now known as Trebinje.
Bt the time the Ottomans arrived, Bosnia had been decimated to such a point that most of the country fell to the Muslims in less than 2 months. People converted to Islam immediately, historians suggest as a means of securing their own survival. The city of Solu (modern-day Tuzla) even sent out a messenger saying the people had converted to Islam and the Ottoman soldiers were welcome, before they even arrived.
That's Bosnia alone, and you will not find a country in Europe with a less bloody history.
Tell that to the monophysites in present-day Egypt.
You really need to take a history course, and quickly, Gloria.