1557: Portuguese seize the strategically important hilltop of Macao at the mouth of the Pearl River. This begins three centuries of near-monopoly over European trade into China. 1839-1842 Britain defeats China in the Opium War. Treaty of Nanjing formalizes the cession of southern Hong Kong to British control. The new British port undermines Macao's dominant trade position. 1849: Portuguese colonial ruler of Macao, Gen. Joao Maria Ferreira do Amaral, is killed by Chinese peasants. 1966: Fanatical Chinese Red Guards storm into Macao to support popular riots. Portuguese officials offer to hand over the colony, but Beijing turns down the offer. 1974: Portuguese government is overthrown in military coup. New leftist government disavows colonialism, offers to return Macao to Beijing; the offer is refused. 1979: China and Portugal normalize relations and agree to recognize Macao as Chinese territory under Portuguese administration. 1987: China and Portugal sign a joint declaration agreeing that Macao will be a special administrative region of China in 1999 run by Macao residents, "enjoying a high degree of autonomy."