The Portuguese increased efforts for occupying the interior of the colony after the Scramble for Africa, and secured political control over most of its territory in 1918, facing the resistance of some Africans during the process.
The region as a whole was long officially termed Portuguese East Africa, and was subdivided into a series of colonies extending from Lourenço Marques in the south to Niassa in the north.
According to the official policy of the Salazar regime, inspired on the concept of Lusotropicalismo, Mozambique was claimed as an integral part of the "pluricontinental and multiracial nation" of Portugal, as was done in all of its colonies to Europeanise the local population and assimilate them into Portuguese culture.
As the Muslim traders, mostly Swahili, were displaced from their coastal centres and routes to the interior by the Portuguese, migrations of Bantu peoples continued and tribal federations formed and reformed as the relative power of local chiefs changed.
Periodic recognition of the relative insignificance of the revenues it could produce was tempered by the mystique which developed regarding the mission of the Portuguese to bring their civilisation to the African territory.
After all of the area of the present province had been recognised by other European powers as belonging to Portugal, administrators waged wars against African polities to assert control over the territory.
The uneducated Portuguese immigrant peasants in urban areas were frequently in direct competition with Africans for jobs and demonstrated jealousies and racial prejudice.
According to Swahili traders whose accounts were recorded by the Portuguese historian João de Barros, Great Zimbabwe was an ancient capital city built of stones of marvellous size without the use of mortar.
At least since the early 19th century, the legal status of Mozambique always considered it as much a part of Portugal as Lisbon, but as a província ultramarina (overseas province) enjoyed special derogations to account for its distance from Europe.
In the 20th century, the province was also subject to the authoritarian Estado Novo regime that ruled Portugal from 1933 to 1974, until the military coup in Lisbon, known as the Carnation Revolution.
Finally, an Economic and Social Council had to be consulted on all draft legislation, and the Governor-General had to justify his decision to Lisbon if he ignored its advice.
Firstly, on 28 June 1919, the Treaty of Versailles transferred the Kionga Triangle, a 1,000 km2 (390 sq mi) territory south of the Rovuma River from German East Africa to Mozambique.
The districts with their respective capitals were:[9] Other important urban centres included Sofala, Nacala,[19] António Enes, Island of Mozambique and Vila Junqueiro.
Most inhabitants were black indigenous Africans with a diversity of ethnic and cultural backgrounds, ranging from Shangaan and Makonde to Yao or Shona peoples.
[20] The indígenas were subject to the traditional authorities, who were gradually integrated into the colonial administration and charged with solving disputes, managing the access to land, and guaranteeing the flows of workforce and the payment of taxes.
Gradually, these traditional titles lost some of their content, and the régulos and cabos de terra came to be viewed as an effective part of the colonial state, remunerated for their participation in the collection of taxes, recruitment of the labour force, and agricultural production in the area under their control.
Within the areas of their jurisdiction, the régulos and the cabos de terra also controlled the distribution of land and settled conflicts according to customary norms.
[24] The largest coastal cities, the first founded or settled by Portuguese people since the 16th century, like the capital Lourenço Marques, Beira, Quelimane, Nacala and Inhambane, were modern cosmopolitan ports and a melting pot of several cultures, with a strong South African influence.
However, prominent architects such as Pancho Guedes fused this with local art schemes giving the city's buildings a unique Mozambican theme.
Indigenous African peasants mainly produced cash crops designated for sale in the markets of the colonial metropole (the centre, i.e. Portugal).
The large availability of capital from both Portuguese and international origin, allied to the wide range of natural resources and the growing urban population, lead to an impressive growth and development of the economy.
The Portuguese-ruled territory was introduced to several popular European and North American sports disciplines since the early urbanistic and economic booms of the 1920s and 1940s.
This period was a time of city and town expansion and modernization that included the construction of several sports facilities for football, rink hockey, basketball, volleyball, handball, athletics, gymnastics, and swimming.
The initial surface of the new track, named Autódromo de Lourenço Marques did not provide enough grip and an accident in the late 1960s killed 8 people and injured many more.
Therefore, in 1970, the track was renovated and the surface changed to meet the highest international safety requirements that were needed at large events with many spectators.
[39] As communist and anti-colonial ideologies spread out across Africa, many clandestine political movements were established in support of Mozambique's independence.
Statistically, Portuguese Mozambique's whites were indeed wealthier and more skilled than the black indigenous majority, in spite of decreasing legal discrimination of Africans starting in the 1960s.
For the Portuguese society the war was becoming even more unpopular due to its length and financial costs, the worsening of diplomatic relations with other United Nations members, and the role it had always played as a factor of perpetuation of the Estado Novo regime.
A leftist military coup in Lisbon on 24 April 1974 by the Movimento das Forças Armadas (MFA), overthrew the Estado Novo regime headed by Prime Minister Marcelo Caetano.
FRELIMO took complete control of the Mozambican territory after a transition period, as agreed in the Lusaka Accord which recognized Mozambique's right to independence and the terms of the transfer of power.