The National Party implemented the system of apartheid, which enforced racial segregation laws, during his tenure as prime minister.

[2] Malan left South Africa in 1900 to study towards a Doctorate in Divinity at the University of Utrecht, which he obtained in 1905.

Malan returned to South Africa, where he was ordained as a minister of the Dutch Reformed Church and served for six months as an assistant-minister in Heidelberg, Transvaal.

B. M. Hertzog, Malan was given the post of Minister of the Interior, Education and Public Health, which he held until 1933.

In 1925, he was at the forefront of a campaign to replace Dutch with Afrikaans in the constitution and provide South Africa with a new national flag.

Malan strongly opposed this merger and, in 1934, he and 19 other MPs defected to form the Purified National Party, which he led for the next 14 years as the opposition.

South Africa's participation in the conflict was unpopular among the Afrikaner population, and in 1939 that led to a split in the governing United Party.

During Malan's tenure as prime minister, South Africans lost the right of appeal from the Appellate Division of the Supreme Court of South Africa to the Judicial Committee of the Privy Council in London under the terms of the Privy Council Appeals Act, 1950.

On 24 February 1953, Malan was granted dictatorial powers to oppose black and Indian anti-apartheid movements.