Inca Civil War

Inca Civil War
Emperor Atahualpa, the victorious brother, however, his reign as emperor was short.
Date 1529 – April 1532 Location Peru and Ecuador Result Atahualpa victory; reunion of the Inca Empire under his rule Weakening of the empire which leads to the Spanish conquest
Belligerents
Huáscar and his allies such as Tumebamba	Atahualpa and his allies
Commanders and leaders
Huáscar (POW)  † Hango † Topa Atao (POW) Ullco Colla † Tito Atauchi Uampa Yupanqui Guanca Auqui Agua Panti Paca Yupanqui	Atahualpa Chalcuchimac Quizquiz Rumiñawi Ukumari Tomay Rima  †
Strength
~400,000; 100,000 Cañaris	Initially 50,000–100,000 At peak some 250,000
Casualties and losses
At least 100,000 killed Tumebamba destroyed	Unknown

The Inca Civil War, also known as the Inca Dynastic War, the Inca War of Succession, or, sometimes, the War of the Two Brothers was fought between two brothers, Huáscar and Atahualpa, sons of Huayna Capac, over the succession to the throne of the Inca Empire. The war followed Huayna Capac's death in 1527, although it did not begin until 1529, and lasted until 1532. Huáscar initiated the war because he saw himself as the rightful heir to the kingdom of all the Incas. Regardless of legitimacy, Atahualpa proved himself to be tactically superior to his brother in warcraft and to the mighty armies of Cuzco, which their father had stationed in the north part of the empire during the military campaign. Accounts from sources all vary in the exact details.

In 1524-1526, the Spaniards under Francisco Pizarro explored South America. There were 62 horsemen and 106 foot soldiers.Smallpox was taken to the continent, causing disaster for the Incas. Sapa Inca Huayna Capac travelled north to investigate the strangers. Although he never met any Spaniards, he contracted smallpox and died in 1524. His eldest son and heir, Ninan Cuyochi, died soon after him. Thus it became uncertain as to who should be the next Inca king. There were no clear rules of succession. The choice stood between two sons of Huayna Capac, Huáscar, and Atahualpa, born of different mothers.

Wayna Qhapaq was king before the dynastic war began; his, along with his sons death (most likely due to smallpox), created the circumstances for a non-appointed king

Huáscar was appointed king by Huayna Capac, and was supported by the nobility in Cuzco, by religious and political authorities and other main figures. He was the eldest "pure" Inca, because his parents, Huayna Capac and Chincha Ocllo, were siblings. Huascar was ill tempered, suspicious and disrespectful of the laws and customs.

Atahualpa's mother, Paccha, was born outside the royal family (although born into the Shyri royal family) and was merely the daughter of Cacha Shyri Duchicela, the former leader against the Incan conquest in the north. He was much liked in the North, as he was good tempered and carried himself with royal dignity. He allegedly had cunning and early wisdom.

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Wikipedia