Complex sentence: Land prices rose substantially, and real estate development became a source of considerable income for Shanghai's westerners, further increasing the westerners' grip over the city's economy, and had been raised the Battle of Shanghai (1861).
Split into simpler sentences: Land prices rose substantially, and real estate development became a source of considerable income for the Shanghailanders, further increasing the westerners'grip over the city's economy. And had been raised the Battle of Shanghai (1861).