Well, Pilgrim, I joked about the question before.
But there is a lot of seriousness in that answer. If you ask if indigenous people, Sikhs, Muslims, Jews, Christians and Bahais, worship a monotheistic God, who created the universe, the answer is Yes.
If you ask - for example - “does the Christian and Muslim God, have the same attributes” - the answer is NO. You just need to read the book What Every Christian Needs to Know About the Qur’an by James W. White, to answer that question. The God of Christianity is a God of grace and forgiveness. The God of Islam has angels count your good and bad deeds and has a system of laws. Hopefully, the good deeds outweigh the bad, at the end of life. Only in their mystical movement of Sufism, does Islam approach Christianity.
To understand more, read the referred book. Or watch the Theosophical Society webcast this Thursday, 1/28/16 at 7 PM CST on Islamic Spirituality: The Role of Religious Law, by a professor in religious studies. He’s at the College of Dupage (with a PhD from Yale). Or watch the rebroadcast, about a week later, at Theosophical Society rebroadcasts
It’s nice that the Faculty advisory board at Wheaton College, recently recommended dropping the termination procedure against the black professor. She said “Muslims and Christians worship the same God”. Perhaps if she hired me to intercede (at the college on her behalf), this would never have become an issue.