Well, while technically Mr Green is correct, the Muslim population in the US was A)Extremely Tiny and B) Slaves. It is not as if many of them had the choice of living here or not. The most famous case of Muslims living in the US is that of Yarrow Mamout, Mamout was a Muslim from Guinea, captured and sold into slavery at 16. He became known as a brick maker, bought his freedom and became quite wealthy before his death. A professor by the name of James H. Johnston recently published a well written biography of Mamout and here's Mamout's 1819 portrait.

Why would you define it as 'fiercely' Christian?