The arrival of Europeans engendered autonomy of small kingdoms which were under the influence of Djolof. Less dependent on trans-Saharan trade with the new shipping lanes, they turn more readily to trade with the New World. The decline of these kingdoms can be explained by internal rivalries, then by the arrival of Europeans, who organized the mass exodus of young Africans to the New World. Ghazis, wars, epidemics and famine afflicted the people, along with the Atlantic slave trade, in exchange for weapons and manufactured goods. Under the influence of Islam, these kingdoms were transformed and marabouts played an increasing role.