The Sapa Inca ("The Great Inca"), also known as Apu ("Divinity"), Inka Qhapaq ("mighty Inca"), or simply Sapa ("The Great One") was the ruler of the Kingdom of Cusco and later, the Emperor of the Inca Empire (Tawantinsuyu). The origins of the position are mythical and tied to the legendary foundation of the city of Cusco but historically it seems to have come into being around 1100. The position was hereditary, with son succeeding father.

There were two known dynasties, led by the Hanan and Hurin moieties respectively. The latter was in power at the time of Spanish conquest. The last official Sapa Inca was Atahualpa, who was executed by the Spanish in 1533, though several of successors later claimed the title.

Little is known of the rulers of the first dynasty of Sapa Incas. Evidently, they were affiliated with the Hurin moiety and their rule did not extend beyond the Kingdom of Cusco. Their origins are tied to the mythical establishment of Cusco and are shrouded in later foundation myth. The dynasty was supposedly founded by Manco Cápac, considered the son of the sun god Inti.

Huayna Capac (1464/1468–1525/1527) was the eleventh Sapa Inca of the Inca Empire and sixth of the Hanan dynasty. He was the successor to Tupac Inca Yupanqui.

In Quechua, his name is spelled Wayna Qhapaq, and in Southern Quechua, it is Vaina Ghapakh. In English, his name translates to the "rich youth" or the "youthful prince." His original name was Tito Husi Hualpa.

Huayna Capac was born in Tomebamba, Azuay Province, Ecuador, possibly in 1488. He was the son of Topa Inca and the Inca's sister and wife.

Huayna Capac's legitimate wife and full sister was Coya Cusirimay. The couple produced no male heirs, but Huayna Capac sired as many as 50 or more children with other women, including Ninan Cuyochi, Huáscar, Atahualpa, Túpac Huallpa, Manco Inca Yupanqui, General Atoc, Paullu Inca and Quispe Sisa, all of whom could be said to be his successors.

Huayna Capac extended the Inca empire (Tahuantinsuyu) significantly to the south into present-day Chile and Argentina. For many years, he and his armies fought to annex territories north of his empire in what is now Ecuador (and a small region of Colombia) to the northernmost province. The capital city of the empire was far to the south in Cuzco, and Huayna Capac hoped to establish a northern stronghold in the city of Tomebamba.