There's a lot that we don't know for sure about the Inca Empire, because we have conflicting accounts among Spanish colonizers, as well as the fact that Inca history itself is told non-linearly. But we do know that they used Andean accomplishments, from architecture to knotted quipu, to create a city that ruled the largest Indigenous empire in the Americas, starting with Manco Capac and the successive Sapa Inca rulers.
Pachacuti, the Earth-Shaker, was the ninth leader of the Inca and the one who took the ambitions of the city of Cusco into an all-out military campaign to expand the empire--alongside bribing and engineering and negotiating their way to expansion.
To understand daily life in the Inca Empire, we travel from Cusco to Quito (located in modern-day Ecuador), where Thupa Inca wanted to establish a second capital city. From efficiently designed work assignments, to elaborate death rituals, life was neatly organized, masking rising tensions.
Disease--likely, smallpox or measles--had arrived in the Inca empire, and it was ruthless. Two of the (now dead) Emperor Huayna Capac's sons, Atahualpa and Huáscar, decided that a civil war over who should be Sapa Inca was perfect to do right now--nevermind the fact that Francisco Pizarro and his conquistadores had just showed up.
Atahualpa vs. Francisco Pizarro. The Incas had never seen horses before, and it wasn't long before the Spanish had captured Atahualpa as a hostage for gold and silver. But Atahualpa had a plan. He found a way to use this situation to his own political advantage--and Pizarro eventually destroyed himself through his greed and violent carelessness that appalled the Spanish government, eventually allowing the Incas to thrive again.