It lasted from about 18 December 1914 to 6 February 1917 with the death of its leader, King Mandume yaNdemufayo, by South African forces in Namibia.

The war pitted Portuguese troops, commanded by General António Júlio da Costa Pereira de Eça, against an Ovambo army, composed mainly of fighters from the Oukwanyama clan.

The Berlin agreements of 1884 split the kingdom and the larger Ovambo ethnic group as a whole between two colonial powers, without any say from any from the native people in Angola.

Due to decades of these illegal arms trades, many of the Ovambo kingdoms owned large amounts of guns and their military capacity was not to be underestimated.

The letter also talked about Germany's "great victories" in Europe, assuring Mandume that if he stayed "faithful to the Germans you need not fear the Portuguese.

The next month on November 5, Mandume allegedly told then-district governor José Augusto Alves Roçadas that the Germans were going to attack Angola.

The victory in their region impressed the Ovambos and encouraged them considered that the time had come to shake off the yoke of the Portuguese colonial occupier.

But no rebellion came until governor Roçadas started to fall victim to the notions of "German military brilliance" and fearing an envelopment moved most of his troops out of the Ovambo region and towards Humbe, leaving behind 1,000 rifles and 4 machine guns.

By the time the Portuguese got there, Ovambo's military capacity had already been reduced due to increased famine and social upheaval build-up over the years.

[19] On 20 August, Mandume assembled several thousand men and attacked the Portuguese camp shouting "The land does not belong to the white[s]!".

After the battle, the Portuguese also started claiming that German forces were helping the Ovambo because it was unimaginable to them that Africans were able to wage war like Europeans.

Pereira de'Eça decided to wait for reinforcements instead of returning to Humbe because the last time Portuguese forces withdrew from the area, it didn't go so well for them.

This caught the attention of South African Prime Minister, General Louis Botha, who was upset by Mandume's actions and told him to explain himself at Windhoek.

In response, Botha was told that Kwanyaman law prohibited the King from leaving his territory and that Mandume thought he had done nothing wrong.

The South Africans, refusing joint operations with the Portuguese, who "thirst[ed] for his blood," sent a force of 700 soldiers under Colonel de Jager to depose Mandume.

By this point, Manning, Lieutenant Carl Hugo L. Hahn, and allegedly Ndjukuma, whom the King had displaced from Oihole to Omhedi, had collected enough information to make a feasible open attack on Mandume.

[3] Finally, on 6 February 1917, machine-gun fire from South African forces killed Mandume near his embala in Oihole, ending the Ovambo Uprising.