"The summary of seven hundred years of Christian expansion on
northern Europe is that the work was mainly done by the sword,
in the interests of kings and tyrants, who supported it, as
against the resistance of their subjects, who saw in the Church
an instrument for their subjection. Christianity, in short, was
as truly a religion of the sword as Islam.
"The heathen, broadly speaking, were never persuaded, never convinced, never won by the appeal of the new doctrine; they were either transferred by their kings into the Church like so many cattle, or beaten down into submission after generations of resistance and massacre. The misery and the butchery wrought from first to last are unimaginable. If the Spanish conquest of Mexico and Peru, with their Church-based policy of suppressing heathenism, be added to the record, the total of evil becomes appalling: for the Spanish Priest Las Casas estimated the total destruction of Native life (in South America) at twelve millions.
"All this slaughter took place by way of expansion, and is exclusive of the further record of the slaughters wrought by the Church within its established field." --- Robertson - History of Christianity.
A study of the history of Christian civilisation, between the time it came into being in 381 until the Renaissance in the 15th century, reveals an arid desert of thought and intelligence. Little literature of any value was produced. There was no education, and all knowledge was considered sinful. Anyone who had an opinion different from that prescribed by the Church was looked upon as a heretic.
Consequently, we read that Jovinian, a Christian Monk of the 4th century, was condemned and flogged by the Church Council because he stated that the virgin Mary ceased to be a virgin after the birth of Jesus. After the flogging, he was excommunicated and banished to desert island.