port and market town in Anambra State, southern Nigeria. The town lies on the east bank of the Niger River just south of its confluence with the Anambra River. Founded by adventurers from Benin (nearby, to the west) in the early 17th century, it grew to become the political and trading centre of the small Igbo (Ibo) kingdom of Onitsha. Its monarchical system (rare among the Igbo people) was patterned after that of Benin. An Onitsha obi ("king") negotiated in 1857 with William Balfour Baikie, a British trader, for the establishment of a British trading post in the town.
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