Complex sentence: Given the Chinese demand for raw goods as well as the American demand for anything remotely exotic, the voyage of the Empress was a financial windfall for its owners and thus began the lucrative Sino-American relationship known as the Old China Trade.
Split into simpler sentences: Given the Chinese demand for raw goods and the American demand for anything remotely exotic, the voyage of the "Empress" was a financial windfall for its owners. This was the beginning of the lucrative Sino-American relationship known as the Old China Trade.