Defining 'Christianity' in the Caribbean

What is Christianity? Who is a Christian?
In this course we will be learning about varieties of historical expressions of Christianity, from Spanish Catholicism to English Anglicanism and the Dutch Reformed Church. Around 1640, numerous church "sects" begin to appear in the Caribbean - first the Quakers in Barbados, then German Moravians in St. Thomas, and then English Methodists and Baptists fleeing from the British defeat in North America after the War of 1812.
"Christendom" is a geo-political form of Christianity that began with Constantine and the recognition of Christianity as the official legal religion of the Roman Empire. Catholics, Anglicans and Dutch Reformed were, to one degree or another, expressions of variations of "Christendom."
After the English Civil War (1640-1660) a group of Christian missionary and reforming movements begin to appear such as Quakers, Moravians, Methodists and Baptists. In classic sociological terms, these groups are not considered to be "Churches" but "sects."
How do we define "Christian"? There is a subjective tendency to identify "Christians" as anyone who looks like us and believes like us, but this is a fallacy. Modern Evangelicals may try to dodge criticism for the Medieval crusades, or the Spanish brutality of conquest in the new world but simply saying "well, they really were not genuine Christians!" and there we fall into problems of definition. They certainly thought of themselves as true Christians by their own contemporary criteria.
So for the purposes of this class, any group is "Christian" if they 1) identify themselves to be Christians, and 2) if they adhere to the early creeds (Apostles creed and Nicene creed).