Short answer
No. Most Muslims are not Arabs. Pew Research Center, a US research group, counted Muslims in 2009. Only about one Muslim in five lived in the Middle East and North Africa. Even that region includes Turkey and Iran, which are not Arab lands. In the same count, Indonesia, Pakistan, India and Bangladesh together had about twice as many Muslims as that whole region. The Companions, the followers who lived with the Prophet Muhammad (ﷺ), came from many peoples. Bilal was an African, Salman a Persian, and Abdullah ibn Salam a learned Jew. The Qur'an speaks to all mankind and says the most honoured person is the most righteous, not the best born. The Prophet (ﷺ) said every earlier prophet was sent to his own nation, but he was sent to all people. Jesus said he was sent only to Israel. So Islam is God's (﷾) message for everyone.
Full explanation
No chosen race
The Qur'an speaks to all mankind. It says God (﷾) made people into nations and tribes so that they would know one another. It also says the most honoured in His sight is the most righteous. Birth and race give no rank before God (﷾).
“O mankind! We created you from a single (pair) of a male and a female, and made you into nations and tribes, that ye may know each other (not that ye may despise (each other). Verily the most honoured of you in the sight of Allah is (he who is) the most righteous of you. And Allah has full knowledge and is well acquainted (with all things).”
A messenger to all people
The Qur'an tells the Prophet (ﷺ) to say that he is the Messenger of Allah (﷾) to all people. It calls him a messenger to all men and a mercy for all creatures. He said that every prophet before him was sent to his own nation only, but he was sent to all mankind. The Qur'an is in Arabic because every messenger spoke the language of the people he was first sent to.
“Say: "O men! I am sent unto you all, as the Messenger of Allah, to Whom belongeth the dominion of the heavens and the earth: there is no god but He: it is He That giveth both life and death. So believe in Allah and His Messenger, the Unlettered Prophet, who believeth in Allah and His words: follow him that (so) ye may be guided."”
“We have not sent thee but as a universal (Messenger) to men, giving them glad tidings, and warning them (against sin), but most men understand not.”
“We sent thee not, but as a Mercy for all creatures.”
Jabir ibn Abdullah reports that the Prophet (ﷺ) named five things given to him that no prophet before him was given. The last of them: every earlier prophet was sent to his own nation only, but he was sent to all mankind.
“We sent not a messenger except (to teach) in the language of his (own) people, in order to make (things) clear to them. Now Allah leaves straying those whom He pleases and guides whom He pleases: and He is Exalted in power, full of Wisdom.”
Where Muslims live
The facts match this teaching. Pew Research Center, a US research group, counted the world's Muslims in 2009. About one in five lived in the Middle East and North Africa. More than six in ten lived in Asia. The four largest Muslim populations were in Indonesia, Pakistan, India and Bangladesh. Indonesia alone has more Muslims than any Arab country. Not every Arab is a Muslim either: millions of Arabs are Christians.
A country-by-country estimate of the world's Muslims in 2009: about 1.57 billion. About one in five lived in the Middle East and North Africa, a region that includes Turkey and Iran, and more than six in ten lived in Asia. The four largest Muslim populations were in Indonesia, Pakistan, India and Bangladesh.
The Prophet's (ﷺ) Companions came from many peoples
It was the same in his own lifetime. The followers of the Prophet (ﷺ) were not all Arabs. Bilal was a freed slave, set free by Abu Bakr, the Prophet's (ﷺ) closest Companion. Umar, the second caliph (leader of the Muslims), called Bilal "our master". Salman came from Persia. Abdullah ibn Salam was the man the Jews of Medina called their most learned. Once a verse spoke of believers who were still to come. The Prophet (ﷺ) put his hand on Salman. He said that even if faith were as far away as the stars of the Pleiades, men of his people would reach it.
Jabir ibn Abdullah reports that Umar used to say: Abu Bakr is our master, and he set free our master, meaning Bilal.
Salman reports that he came from Ram-Hurmuz, a town in Persia.
Anas reports that Abdullah ibn Salam, a Jew of Medina, tested the Prophet (ﷺ) with three questions that only a prophet could answer, then bore witness that he was the Messenger of Allah. Before they knew of it, the Jews of Medina described Abdullah to the Prophet as the most learned and the best of them.
Abu Huraira reports that when Qur'an 62:3 was revealed, speaking of others who had not yet joined the believers, he asked the Prophet (ﷺ) who they were. The Prophet put his hand on Salman the Persian and said that even if faith were as far away as the Pleiades, a group of stars, men from these people would reach it.
It was Jesus who was sent to one nation
The one sent to a single nation was Jesus. In the Gospel of Matthew, he says he was sent only to the lost sheep of the house of Israel. He told the twelve, his chosen disciples, not to go to the Gentiles (people who are not Jews). He also told them not to go to the Samaritans (a people of Samaria, between Judea and Galilee). The Qur'an agrees, calling him a messenger to the Children of Israel. The message for all nations came with the Prophet (ﷺ) who came after him. Christians point to Matthew 28:19. There Matthew reports that Jesus told the eleven (the twelve disciples without Judas) to teach all nations. But the Book of Acts tells how, years later, Peter, the leading disciple, still called it unlawful for a Jew to visit a Gentile. He went only after a vision, and the believers in Jerusalem found fault with him for going. If Jesus had openly sent the eleven to all nations, neither Peter nor the believers would have hesitated. The page 'Was Jesus sent to all nations, or only to Israel?' gives the full answer.
“But he answered and said, I am not sent but unto the lost sheep of the house of Israel.”
“These twelve Jesus sent forth, and commanded them, saying, Go not into the way of the Gentiles, and into any city of the Samaritans enter ye not: But go rather to the lost sheep of the house of Israel.”
“"And (appoint him) a messenger to the Children of Israel, (with this message): "'I have come to you, with a Sign from your Lord, in that I make for you out of clay, as it were, the figure of a bird, and breathe into it, and it becomes a bird by Allah's leave: And I heal those born blind, and the lepers, and I quicken the dead, by Allah's leave; and I declare to you what ye eat, and what ye store in your houses. Surely therein is a Sign for you if ye did believe;”
“Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost:”
“And he said unto them, Ye know how that it is an unlawful thing for a man that is a Jew to keep company, or come unto one of another nation; but God hath shewed me that I should not call any man common or unclean.”
“And when Peter was come up to Jerusalem, they that were of the circumcision contended with him, Saying, Thou wentest in to men uncircumcised, and didst eat with them.”
Perspectives
The Islamic perspective
Islam is God's (﷾) message to all mankind. The Prophet (ﷺ) was sent to every nation, and his followers from the first day came from many peoples. Today most Muslims are not Arabs.
In a 2009 count by Pew Research Center, most Muslims lived in Asia. Only about one in five lived in the Middle East and North Africa.
The Prophet's (ﷺ) Companions included Bilal, a freed slave, and Salman the Persian. They also included Abdullah ibn Salam, a learned Jew of Medina.
The Qur'an teaches that the most honoured person in God's (﷾) sight is the most righteous. This is so whatever his nation or tribe.
The Qur'an teaches that the Prophet Muhammad (ﷺ) was sent to all people.
The Prophet Muhammad (ﷺ) said earlier prophets were sent to their own nations, and he to all mankind.
In Matthew, Jesus says he was sent only to Israel and tells his disciples not to go to the Gentiles.