Huayna Capac (1493 - 1527) was an Inca emperor. He was the successor to Tupac Inca Yupanqui. He was also the father to Huascar, Atahualpa, Tupac Huallpa, Manco Inca Yupanqui and Paullu Inca .

Huayna Capac extended Tahuantinsuyu, the Inca empire, during his reign. For many years he and his armies fought in the far north of the empire in what is now the country of Colombia. The capital city of Tahuantinsuyu was far to the south in Cuzco, and Huayna hoped to establish a northern stronghold in the city of Quito.

Around 1527, Huayna Capac's was in Columbia and he and his troops became plagued with illness and thousands died of what was probably smallpox. Both Huayna Capac and his heir Ninan Cuyochi died. Huascar was already working to overthrow Ninan when he learned of his death. He quickly secured power in Cusco, and had Atahualpa arrested. But Atahualpa escaped with the help of a little girl and began securing support from Huayna Capac's best generals, who happened to be near Quito, the nearest city to Columbia. A civil war ensued with Atahualpa being victorious, but it was at this time that Spanish conquistadors began arriving in South America and they used deceit to capture Atahualpa before he had returned to Cusco, copying an earlier exploit in Mesoamerica. A series of missteps by his generals following his capture led to the quick downfall of the empire.

The kill rate of smallpox in the Americas is disputed, but it was higher than in Europe where it related plagues had strenghened immune systems. Anywhere from 60% to 90% of the Amerindians died of smallpox and other European plagues in the first years after their introduction to the Americas. Large well connected empires like the Aztec and Inca empires were the most susceptible.