William Sacks wrote to ask about primary sources regarding enslaved
African people who were Muslims. While this is not my area of
expertise, I know that Davidson College in North Carolina has in
their rare book room a copy of the Christian Bible written in Arabic
script which was copied by/for enslaved people on a Carolina
plantation and came to the college from the library of that
plantation. For many years, Davidson did not know what "that Arabic
book" was until they hired a religion professor who read Arabic and
identified it.
I have looked also at 19th-century naming practices in African
communities in the United States, which also exhibit some degree of
Islamic influence and identity. African American Christian- ity also
reflects to a great degree an Islamic orientation in that many of the
most favored stories and motifs are those that are common to both
Islam and Christianity.
I think many people carelessly regard African "conversion" as an
abandonment of past tradition without recognizing that Moses,
Abraham, Daniel, Elijah, Jesus, etc. are all important figures in
Islam and the Koranic tradition--and some of the modal presentations
of African American religious music reflect African Islamic
traditions as well.
As for the percentage, that is probably regionally variable--the rice
coast of the Carolinas and Georgia certainly had a large Islamic
population since the SeneGambian rice coast was the source of
cultivation techniques and the favored point of origin for "dealers"
and "buyers" of forced labor in that area.