The establishment of the Northern and Southern Protectorate in the early 20th century refers to the division of Nigeria into two separate administrative regions by the British colonial authorities. This division was a result of the British colonization of Nigeria, which began in the late 19th century.

Background
In the late 19th century, the British colonized various parts of Nigeria, which was then a collection of independent kingdoms and empires. The British colonization of Nigeria was driven by the desire to expand their empire, exploit Nigeria's natural resources, and spread Christianity. By the early 20th century, the British had established control over most of Nigeria, but they faced challenges in administering the vast territory.

The Establishment of the Protectorate
In 1900, the British government divided Nigeria into two separate protectorate: the Northern Protectorate and the Southern Protectorate. The Northern Protectorate consisted of the Hausa-Fulani emirates in the north, while the Southern Protectorate comprised the Yoruba and Igbo kingdoms in the south. The division was based on the cultural, linguistic, and geographical differences between the two regions.

The Northern Protectorate
The Northern Protectorate was established in 1900, with Lord Frederick Lugard as its first High Commissioner. The protectorate was characterized by a feudal system, with the Emir of Kano as the paramount ruler. The British colonial authorities maintained a policy of indirect rule, which allowed the traditional rulers to maintain their powers and influence. The Northern Protectorate was largely Muslim, and the British authorities respected the Islamic traditions and institutions of the region.

The Southern Protectorate
The Southern Protectorate was also established in 1900, with Sir Ralph Moor as its first High Commissioner. The protectorate was characterized by a more direct system of rule, with the British colonial authorities exercising greater control over the local population. The Southern Protectorate was largely Christian, and the British authorities encouraged the spread of Christianity and Western education.

Consequences of the Division
The division of Nigeria into two protectorate had significant consequences for the country. The division created a sense of separate identities and interests among the people of the north and south, which would later contribute to the country's political and ethnic tensions. The division also led to unequal development, with the north receiving more attention and resources from the British colonial authorities.

Amalgamation of the Protectorate
In 1914, the British government amalgamated the Northern and Southern Protectorate to form a single colony, known as the Colony and Protectorate of Nigeria. The amalgamation was driven by the need to create a more efficient and centralized system of administration. However, the amalgamation did not erase the cultural and geographical differences between the north and south, and the legacy of the division continued to shape Nigeria's politics and society.