No Islam was not spread by sword.

As Qur'an says, "There is no compulsion in Religion""

Let there be no compulsion in religion: Truth stands out clear from error" [Al-Qur’an 2:256]

Islam is the religion of the Truth. The Qur'an is the book of the Truth.
"We sent down the Qur'an in Truth and in Truth has it descended." (17:105)

"Put your trust in Allah for you are on the path of the manifest Truth."(27:79)

Islam stands for peace, force is used in order to restore peace, justice and rule of law.
As Hazarat Abu Bakr Siddique fought against those people who denied to pay zakat and were creating disturbance in the Islamic State.

Muslims ruled Spain for about 800 years. The Muslims in Spain never used the sword to force the people to convert. Later the Christian Crusaders came to Spain and wiped out the Muslims. It is mentioned in detail in Naseem Hijjazi’s book “kaleesa or aag”

Indonesia is a country that has the maximum number of Muslims in the world. The majority of people in Malaysia are Muslims. May one ask, "Which Muslim army went to Indonesia and Malaysia?"

Muslims ruled over India for about 800 years but there are still the followers of other religions in the subcontinent. If it was spread by sword then there would be only Muslims in this region.

Islam was spread by the sword of intellect.
Invite (all) to the way of thy Lord with wisdom and beautiful preaching; and argue with them in ways that are best and most gracious." [Al-Qur’an 16:125]

Today the fastest growing religion in America is Islam. The fastest growing religion in Europe is Islam. Which sword is forcing people in the West to accept Islam in such large numbers?