As this is a contentious topic, there are several different answers.
Answer 1
The question of Islam's spread by Sword is a very complex one. The Muslim faith has often been credited as a religion spread by force and coercion.
The question, if answered in a logical way, has two answers: Yes & No. Let us take a look at the 'Yes' first,
"Unlike Christianity, which preached a peace that it never achieved, Islam unashamedly came with a sword."
-Steven Runciman (1903 - 2000)
Muhammad, the founder and prophet of Islam, began preaching his visions in Mecca (in present-day Saudi Arabia) in 610. Within 25 years he and his supporters, called Muslims, had gained control of the whole Arabian Peninsula.
By 650 A.D. a structured Islamic state ruled the Arabian Peninsula, the entire Fertile Crescent and Egypt; by the early 700s Islam subjugated a wide area, stretching from the edges of China and India in the east to North Africa and Spain in the West.
This rapid spread of the religion was due to two factors: Conquest & Conversion. These two ideas were mutually dependent. The former, no doubt, was a contributor to the propagation of Islam.
In the later days of Islam, many tyrants started converting their subjects to Islam by force. These conversions didn't take place in very large numbers and cannot be held responsible for such a great populace of Muslims throughout the world.
Conclusion: It is an irrefutable fact that a portion of the Muslim populace (a very small one) was converted by force.
And now for the 'No':
"Every new opinion, at its starting is precisely in a minority of one. In one man's head alone. There it dwells as yet. One man alone of the whole world believes it, there is one man against all men. That he takes a sword and try to propagate with that, will do little for him."
-Thomas Carlyle (1795-1881)
As pointed by Carlyle, It is impossible for an idea to spread by force. There must be some logic to it that tempts the conscious and subconscious of people and makes them accept it. So is it with Islam.
When an Idea is deeply rooted in the mind, it is impossible to replace it with the use of force. Force only reduces the allure of an idea, no matter how great it is. Even if a person is coerced into believing a notion, he will never accept it by heart.
De Lacy O'Leary rightly said that "History makes it clear that the legend of fanatical Muslims sweeping through the world and forcing Islam at the point of the sword upon conquered races is one of the most fantastically absurd myth that historians have ever repeated."
If Islam was spread by sheer force, then how can you explain these facts?
1. In spite of Muslim dominion of the Arabian Peninsula and neighboring countries, 14 million Arabs belong to the Coptic Christian Church.
2. Indonesia is the country with the largest Muslim population. It is a historical fact that no Muslim Army ever entered Indonesia.
3. Muslims ruled India for nearly a millennium. Today 80% of the Indian populace is non-Muslim (primarily Hindu).
4. Muslims ruled Spain for some 800 years. When they left the country, the majority of the population was Christian.
5. In the mid portion of the last century, the amount of Muslim population increased rapidly. Which war forced such large amount of converts?
6. Today, Islam is the fastest growing religion in U.S.A. Which war is causing this huge proliferation in the population of Muslims?
The answer is clear. Sword was and is being used to convert people to Islam but this is the sword of intellect, not of coercion.
An appropriate analogy
During the Portuguese colonization of the Indian subcontinent, the Christian preachers were able to convert many people to Christianity (especially in Goa). After some decades, they started the Inquisition of new converts. Instead of an increase in the number of converts, there was a rapid decrease in number of converts to Christianity and a rapid increase of converts from Christianity.
Conclusion: The notion that Islam was spread by sword is as absurd as the notion that the Christian faith was spread by thumbscrews.
The above arguments were all from facts; let's now explore the idea of forced conversion in the context of the Islamic set of beliefs.
The word 'Islam' itself means peace. According to the faith, it is haram to force anybody to the convert to Islam. The Lord proclaims straightaway in the Holy Qur'an that:
"The truth is from your Lord; so let whosoever will, believe, and let whosoever will, disbelieve"( 1 8.28).
These words prove that the very essence of Islam is against the notion of forced conversion and depends upon the free will of a person. It is also said in the Qur'an that:
"Let there be no compulsion in religion: Truth stands out clear from error" (2:256)
Even if the rightful Muslims were tempted to resort to the use of force, they were prohibited from using it by the proclamation of the Lord.
Conclusion: The idea of forced conversions is against the essence of Islam. No fair Muslim will ever resort to such a heinous method.
In a nutshell; it can be said that the overall spread of Islam was not due to the sword, as is regurgitated by most Western historians but due to some other factors among which the effective preachers are one.
Answer 2
The alternative answer that is not conveniently skewed to hide the truth from an Islamic bias, is based on the Hindu historic records which proves that the Muslims invaded their country and destroyed many aspects of their beliefs and culture forcing them to convert even terrorizing, raping, pillaging/plundering their society.
It was just after the reign of Emperor Ashoka who created a Buddhist society.
There are many honest historic records of war where the Hindu kings fought against the oppressive Muslims who conquered and forcibly converted their citizens.
It is an established fact that the Abrahamic religions were always driven by the directive to forcibly convert others to their belief system. It is also evident in the laws of the land where Abrahamic beliefs dominate Governance.
The evidence of such behaviors with respect to Abrahamic followers, continue to be the cause of religious wars around the world up to the present time. A person simply has to look at the wars in many countries to realize the fact that religious greed and prejudices are usually at the root of it.
Answer 3
Islam was also a political force, i.e the Islamic Caliphates. The armies of these Caliphates were also fighting an expansionary war for territory just as every other empire did in those days. As the above answers note, the call to "convert or die" was very rare, but when countries were annexed to the Caliphates, many citizens did convert either because they saw the Truth of the religion or to gain from the tax, work-related, and legal benefits that came from conversion.
Many Muslims claim that these empires expanded peacefully. They did not, but by the sword as no country just opens it doors to a new power. In fact, Muslims are very proud of their conquest of the Byzantine Empire and the "liberation" of its territories.
While the religion of Islam did not usually expand through forcible conversion, it is not a ridiculous assertion to say that forcible conversion works. Europe did this in many places which is what assured the strength of Catholicism in Spain, Austria, and France as opposed to Protestantism which grew organically in each of those territories. As for citing Qur'anic verses in support of this idea, there is also verse 9:5 which is the famous "kill them wherever you find them" verse. Of course, Islamic Empires have typically been more tolerant (and thus more approving of the "no compulsion" verse) but the treatment of non-Muslims by Muslims was conditioned more on the governmental powers at any one time than by actions proscribed in the Qur'an since the Qur'an could sensibly be read either way. As to the Goa Analogy, since the Portuguese only controlled Goa, the Indian converts could easily flee to non-Portuguese controlled areas, but when you have an Empire whose borders stretch across timezones without break, there is no way to escape and so you are forced to deal with whatever the government may send your way.
The statistics on Western Conversion to Islam are taken out of context. In many Muslim countries it is either by law or by de facto societal conduct that conversion out of Islam to other religions (such as Christianity) is forbidden and punishable by death. On top of that, proselytization of these non-Muslim faiths is also punishable by long jail terms. As a result, Muslims who realize the Truth of other religions are few and far between and those who would admit to doing so are even rarer. Compare that to Western countries where conversion out of Christianity is barely even a consideration among other Westerners and certainly not something worth killing over.
Furthermore, the Apologist's "facts" need a little more clarification:
1. In spite of Muslim dominion of the Arabian Peninsula and neighboring countries, 14 million Arabs belong to the Coptic Christian Church. --> True, but what happened to all of the Christians who lived in Tunisia (Tunis was an important Christian city). What happened to all of the Moroccan Jews (there were 260,000 in 1940 and there are now 3,600)? What happened to the Christian population of Anatolia? The fact that there are some Arab Christians left does not mean that force was not used, but merely that the result of the use of force has not fully achieved its goal. In October of 2012 another Coptic Church in Egypt was bombed (as is typical) and there was no recourse for Copts other than to flee.
2. Indonesia is the country with the largest Muslim population. It is a historical fact that no Muslim Army ever entered Indonesia. --> True, accept for the Muslim armies that were constructed by Muslim Indonesians. Commerce and peaceful religious acquisition was only a beachhead. It took centuries of Sultanates and repressive policies in Indonesia to convert most Indonesians to Islam. Even today, Indonesian Islam is the most syncretic forms of Islam outside of Africa since not all of the local culture has been successfully purged.
3. Muslims ruled India for nearly a millennium. Today 80% of the Indian populace is non-Muslim (primarily Hindu). --> Using the population of India alone is disingenuous. Muslims controlled Pakistan and Bangladesh as well as India as part of one unified Empire. If the populations of Pakistan and Bangladesh are added to India, the subcontinent is 35% Muslim, which makes sense given that Muslims only occupied the area for less than 500 years and internal information movement in India is very slow given a high terrain difficulties. This is why the largest Muslim populations were along Rivers where major cities were built by the Mughal. The closer to such a population center, the more likely a person would be compelled to convert. Akbar was known for his tolerance and reviled by Muslims for it although loved by non-Muslim Indians. His grandson Aurangzeb was known for compelling conversion and loved by Muslims for it and hated by non-Muslim Indians.
4. Muslims ruled Spain for some 800 years. When they left the country, the majority of the population was Christian. --> True, but there was never a major intent to convert Spaniards. Also between 1293 and 1492, the only area under Muslim control was Granada which meant that most Muslims were under Christian rule. Many of them converted to Christianity in order to reap the benefits of being Christian in a Christian society and to avoid the various massacres that occurred in 14th and 15th century Spain against Muslims.
5&6. In the mid portion of the last century, the amount of Muslim population increased rapidly. Which war forced such large amount of converts? Today, Islam is the fastest growing religion in U.S.A. Which war is causing this huge proliferation in the population of Muslims? --> Yes, multi-culturalism in the West has allowed Islam to come to various countries and expose new people to its religion. We would see the same going on in Islamic Countries if they were open to multi-culturalism. However, since they refuse to allow proselytization of other faiths within their borders and openly murder Muslims who leave Islam, most Muslim conversion to Christianity is minimal and kept secret to avoid death. The fact that Muslims are compelled to stay Muslims by force is just as problematic as forcibly converting non-Muslims to Islam.
Answer 1
There was never the concept of "convert or die"; it is mentioned explicitly in Quran that no compulsion in religion and forcing anyone to convert to Islam is completely prohibited and sinful.
Answer 2
There are certainly debates and arguments that forcible is or is not acceptable Islamic practice. However, this is not about whether or not it is acceptable to forcibly convert people to Islam according to Islamic principles, but about whether or not forcible conversion was actually used -- and it was. It was not the primary way of getting converts, this was through (1) evangelizaton and (2) economic and political pressure that was applied to make conversion attractive.
Some particular events of forcible conversion in Islam:
The Amazigh people, often improperly called "Berbers" or "Moors" were the indigenous North African population who were conquered by the Arab Muslim armies and converted to Islam.
one day when he was in jail...his brother reginald, who had recently converted to islam, visited him and preeched it to him. he finally found his spritual home he'd been looking for all his life. he gladly converted immediately! ! :)
Yes he did, he converted to black islam aka the nation of Islam. He was also a member of the UNIA and the OAAU
Islam
Arabs converted to Islam before Persians did. By 633 CE, almost all Arabian Arabs were Muslims, but almost all Persians were Zoroastrians.
She converted to Islam when married to Imran Khan.
Sure, there are Christians who converted to Islam. Refer to the link below.
Yes he has converted in islam, And changed his name as Waleed!
He converted to Islam.
Yes. He converted to Islam in 1998. He named his sons Suleyman and Ibrahim.
Okay, firt of all, Sunnis are the only Muslims. You probably expected me to say Shi'a (Shi'ite) Muslims, but they are NOT muslims. They do not properly follow Islamic theology and teeachings, so they are considered nonmuslims. I hope I don't offend anyone.
King Clovis did not convert to Islam. Instead, he converted to Christianity, which was the religion of the people of Gaul.
No, Sachin Tendulkar is an Indian and a firm believer of Hindu. He will never get converted to Islam.
He did, but later converted out of Islam.
Traders in Africa had contact with Arabia and converted to Islam
Upper classes converted to Islam!
no