evidence: Countries have wrangled over territory in the South China Sea for centuries, but tension has grown in recent years. [...] Vietnam hotly disputes China's historical account, saying China had never claimed sovereignty over the islands before the 1940s. Vietnam says it has actively ruled over both the Paracels and the Spratlys since the 17th Century - and has the documents to prove it. [...] Malaysia and Brunei also lay claim to territory in the South China Sea that they say falls within their economic exclusion zones, as defined by the United Nations Convention on the Law of the Sea, or UNCLOS.