 Igboland was gradually rebuilt by its citizens and some contribution from the Nigerian government over a period of twenty years and the economy prospered again due to the rise of the petroleum industry in the adjacent Niger Delta region . This led to the establishment of new factories in southern Nigeria . Many Igbo people eventually took government positions , although many were engaged in private business . Since the early 21st century , there has been a wave of Nigerian Igbo immigration to other African countries , Europe , and the Americas . 
