the sparse population, and the popularity of the slave trade in the region made the journey from Makun to the Niger Delta risky. Pirates, mostly Ijo but also including groups drawn from Ijebu and Ilaje villages, were exploiting the relative loneliness of the lagoon and creeks, and the lack of effective governance to prey on traders. By the sixteenth century the Western Niger Delta was known as a pirate den. In 1699, David de van Nyendaal, a Dutch trader who visited the Benin Rivers, referenced the activities of Ijo pirates whom he called the corsaire d'Usa. In the 1780s, the French trader and colonist, Jean-François Landolphe made similar comments about violence on the Benin waters amidst fighting between Ijo, Benin and Yoruba traders. ${ }^{10}$ In perhaps the best historical study of the Ijo, Ebiegberi Alagoa linked the violence to Ijo outward migration. The influx of Arogbo and Apoi (or western) Ijo into hitherto Benin and Yoruba spheres of influence created chaos as they competed with their hosts for supremacy, and scarce salt making, fishing and canoe building sites. By the eighteenth century some Ijo migrants had advanced west as far as Lagos. Competition for territory and resources led to conflicts. ${ }^{11}$ The rise of the Atlantic slave trade in the Niger Delta after 1750 further complicated matters, as key trade ports Warri and Bonny created a huge market for war captives. In effect, piracy became a profitable vocation as bandits seized goods, canoes and sold their captives into slavery. Landolphe recorded an incident in the 1780s when Ijo pirates seized about 200 Yoruba traders. ${ }^{12}$