Why did Indians, China and Japanese emigrate to Africa?

Indians have a huge immigrant group in East Africa, especially in coastal countries and island areas, which has both historical and geographical advantages. Historically, many countries in East Africa and South Africa, like India, were colonies of the British Empire, and Indians were brought to Africa by the British. Geographically, just as China people will go to Nanyang, there are the most overseas Chinese in Southeast Asia today, and Indians "go to Nanyang" and go to Africa.

China and Japanese only appeared in Africa in modern times, which is closely related to global business activities in recent years.