BEIJING (AP) — China’s deployment of an oil rig off Vietnam’s coast near the Paracel Islands has prompted a tense sea standoff and touched off deadly anti-China rioting. The conflict pits two neighbors with very similar governments but whose people bear ill feelings rooted in a rivalry that dates back centuries and has occasionally burst out into armed conflict.

THE ANCIENT HISTORY: Vietnam was ruled off and on for more than a millennium by Chinese dynasties who regarded the southern region as a conquered province. That formally ended in 938 with the defeat of a Chinese force, although China briefly annexed Vietnam again during the Ming Dynasty in the 15th century.