I know that homo sapiens were around during the last Ice Age. Was knowledge of the Ice Age prevalent amongst ancient civilizations, such as the Romans, or did it not become known until much later?
No. The first civilisations with recorded histories didn't come into being until at least 9000 thousand years after the end of the Ice Age. The people that lived through it might not even have been aware of it, because the final deglaciation took place over about two thousand years, and the climate had been gradually warming for ten thousand years before that.
Our understanding of global climate cycles and the last Ice Age comes is a product of modern science. Specifically, early geologists in the 18th century observed out-of-place boulders of Alpine rock far from the Alps, and deduced that they must have been carried there by glaciers, which therefore must have been once much greater in extent. The naturalist Louis Agassiz (1807–1873) seized on this idea and postulated a global "Great Ice Age", when ice sheets covered much of Europe, to explain various geological features that were conventionally ascribed to a biblical Great Flood. On closer inspection of the sedimentary record geologists realised that there were actually several ice ages separated by warm periods, rather than a single Great Ice Age, but on the whole embraced Agassiz's theory. However, the final pieces of the puzzle didn't slot into place until the 1960s, when scientists were able to use deep sea sediment cores and radiometric dating to delineate and precisely date the cycle of glaciations ("ice ages") and interglacials that has been ongoing for the last 2.6 million years; including the last Ice Age (110,000–12,000) and the current interglacial.