How did Christianity change older Baltic ideas about the world ocean?

In the context of Baltic religion, the ancient belief that the Earth was a round plate swimming upon a world ocean is a concept that has largely disappeared due to the influence of Christianity.1

While Baltic folklore has preserved many traditional religious concepts that were lost elsewhere, the introduction of Christian interpretations significantly impacted the documentation and understanding of these older cosmological ideas. Because historical records regarding Baltic beliefs were primarily compiled by foreign writers during and after the Christianization of the region, these documents often reflect a negative or dogmatic view of indigenous traditions, leading to the erosion or reinterpretation of original mythological frameworks.21