Battle of Mbwila At the Battle of Mbwila ( or Battle of Ambuila or Battle of Ulanga ) on October 29 , 1665 , Portuguese forces defeated the forces of the Kingdom of Kongo and decapitated king António I of Kongo , also called Nvita a Nkanga . Origins of the War . Although Kongo and Portugal had been trading partners and participated in a cultural exchange during the sixteenth century , the establishment of the Portuguese colony of Angola in 1575 put pressure on that relationship . Kongo initially assisted Portugal in Angola , sending an army to rescue the Portuguese governor Paulo Dias de Novais when his war against the nearby African kingdom of Ndongo failed in 1579 . But subsequently as Portugal became stronger it began to press harder , and in 1622 severed even the cautiously friendly relationship of the earlier period when a large Portuguese army invaded southern Kongo and defeated the local forces at the Battle of Mbumbi . Pedro II , king of Kongo at the time , responded by personally leading a force at the battle of Mbamba crushing the invasion . He then wrote to the Dutch Estates General , proposing an alliance with the Dutch to drive the Portuguese out of Angola altogether . This alliance did not finally come to fruition until 1641 when Dutch forces took Luanda and were joined by an army from Kongo , forcing the Portuguese to withdraw into the interior . However , they were not able to finish the Portuguese and as a result the Portuguese eventually forced the Dutch out in 1648 . In the years following the Dutch withdrawal , Angolan governors sought to obtain revenge against Kongo and to support the slave trade with a highly aggressive policy . Included in this policy were attacks on the zone of small , semi - independent states called Dembos that separated Angola from Kongo . Both Kongo and Angola claimed authority over the Dembos . King António I , an aggressive monarch in his own right , was negotiating with Spain to renew an anti - Portuguese alliance , and also sent ambassadors into the Dembos areas to persuade them to join Kongo against the Portuguese , promising Spanish aid . In 1665 , one of these small kingdoms , Mbwila , underwent a succession struggle and the various factions appealed to Kongo and Angola for aid . Both sides responded with armies . The battle . The core of the Portuguese force , commanded by Luís Lopes de Sequeira , was 450 musketeers and two light artillery pieces . There were soldiers from the Portuguese colony of Brazil , including some of African and Native American origin , as well as Imbangala and other African forces numbering about 15 , 000 . The Kongo army included a large number of peasant archers , probably about 15 , 000 , some 5 , 000 heavy infantry equipped with shields and swords , and a musket regiment of 380 men , 29 of them Portuguese led by Pedro Dias de Cabral . Both armies were operating at some distance from their main bases . They had marched for days to reach the battlefield , along the valley of the Ulanga River just south of the capital of Mbwila . Steep hills and the river defined the east side of the battlefield , and lower ridges the west . The Portuguese forces took up positions between the two , with their African forces deployed on the flanks and the musketeers forming a diamond shaped formation in the center , anchored by their artillery . The Imbangala forces were held in reserve . António ' s army advanced into the Portuguese formation with a vanguard , followed by three divisions of his heavy infantry and the archers on the flanks . The Duke of Bengo commanded the reserve . In the initial stages of the battle , the Kongolese archers swept most of the African archers of the Portuguese forces from the field and then launched attacks against the Portuguese musketeer s , supported by their own heavy infantry and musketeers . In spite of heavy fighting , the Kongolese were unable to break the Portuguese formation and António was killed in the final attempt . Most of the Kongo forces broke following the king ' s death . The survivors were only able to withdraw thanks to skillful rearguard action by the Duke of Bengo and the reserves . More than 400 of Kongo ' s heavy infantry were killed in the encounter and many more of the archers . Along with these losses was the royal chaplain , the mixed race Capuchin priest Francisco de São Salvador ( Manuel Robrerdo in secular life ) . King António ' s young son of seven years was captured . After the battle , the head of the king or Manikongo was buried with ceremony by the Portuguese in the chapel of Our Lady of Nazareth situated on the Bay of Luanda , and the crown and sceptre of Kongo were sent to Lisbon as trophies . Portugal obtained an act of vassalage from D . Isabel , the regent of Mbwila , but was unable to exercise any real authority over the region once their forces had withdrawn . In 1693 they had to return to attempt to subdue the region again . The primary result in Kongo was that the absence of an immediate heir spun the country into civil war . This civil war , which raged for half a century , led to Kongo ' s decentralization and fundamental changes , leading to Kongolese historians , even in 1700 , regarding the battle as a decisive turning point in their country ' s history .