"Religion was an integral part of early Portuguese colonialism," Evans told Live Science. "People were competitively building churches. You also have religious orders establishing themselves in the early 16th century, and Cidade Velha becomes the seat of the bishopric of Africa."
Slaves may not have been excluded from religious life in Cape Verde. Already, isotope analyses of teeth suggest that many of the people buried under the church were African, and likely slaves.
"The fact that they're getting a church burial could be evidence that converting the slaves to Christianity meant something," Evans said. Further investigation of the bones could reveal more about the work conditions and the diets of the slaves, shedding light on slavery in a late medieval context.
While the main church was built during the decade straddling 1500, there are some early stone foundations from a Gothic chapel that date back to around 1470, which would make it the earliest building on the Cape Verde islands, Evans said.
Since the colonizers were the first people to inhabit the island, they had no knowledge of the local environment, and they made some critical mistakes when building the church. First, they built it on top of a seasonal stream course. Second, the church was located at the bend of a river. These factors made the building vulnerable to flash floods, and the church had to be rebuilt twice in the 16th and 17th centuries, Evans said.
"Instead of being a normally proportioned church, it became a rather fat, squat church," Evans said. "It's a reflection that they didn't understand the landscape they were in."
Pirate attacks eventually caused the downfall of Cidade Velha in the 18th century, but this church was likely reduced to ruins by floodwaters.
"Everyone attributes to demise of Cidade Velha to pirates," Evans said. "In this case, it's actually nature."
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