There are several reasons for the fall of the great empires in Latin America. Let's look at some of them.
One of the first encounters between Europeans and the Incas happened in 1525 and the coming years. This is the time when the Spanish started to explore the Pacific and change the livelihood of Incas for a long time to come (Pillsbury, 2018, p. 9).
We can account the fall of the two empires to at least three reasons – diseases, alliance and advanced military technologies. However, it would be complex to evaluate which of these were more impactful than the others. If we focus on Inca empire, for example, citing Alconini and Covey (2018): “The Inca conquest was not equal everywhere, and it was met with varying indigenous reactions that ranged from endemic episodes of rebellion to clientelism, inter-elite competition, and even emulation and ethnogenesis” (p. 471).
Reason 1 – diseases
European diseases, particularly smallpox, spread through the Inca Empire even before direct contact with the Spanish. Smallpox and other diseases (like measles and influenza) were introduced by Europeans and decimated the indigenous population, who had no immunity to them. The death of Huayna Capac from smallpox contributed to the civil war between his sons (Riedel, 2005, p. 21).
Reason 2 – alliance and internal conflicts
Before the arrival of the Spanish, the Inca Empire
was already weakened by a devastating civil
war between two brothers, Atau Huallpa and Huascar, who were both claiming the throne. The war started around 1527, after the death of the previous emperor, Huayna Capac. The conflict divided the empire, depleted its resources, and weakened the Inca leadership, making it vulnerable to external threats (Alconini & Covey, 2018, p. 475). Citing Rowe (2015): “Spaniards… kidnapped the winner, Atau Huallpa. The leaders of the losing side, who had supported his brother Huascar, asked the Spaniards for help” (p. 27), showing one of many alliance trials between indigenous and colonialist sides.
Reason 3 – advanced military technologies
The combination of steel weapons, horses, firearms, and tactical strategies gave the Spanish a significant advantage over the Inca, who were overwhelmed despite their numerical superiority. This disparity, coupled with internal political instability and the spread of disease, made the Inca conquest relatively swift and decisive (Shuker, 2016, p. 10).
References:
Alconini, S., & Covey, A. (2018). Conclusions: Inca imperial identities: Colonization, resistance, and hybridity. In S. Alconini & A. Covey (Eds.), The Oxford handbook of the Incas (online ed.). Oxford University Press. https://doi.org/10.1093/oxfordhb/9780190219352.013.55
Pillsbury, J. (2018). Writing Inca history: The colonial era. In S. Alconini & A. Covey (Eds.), The Oxford handbook of the Incas (online ed.). Oxford University Press. https://doi.org/10.1093/oxfordhb/9780190219352.013.37
Riedel S. (2005). Edward Jenner and the history of smallpox and vaccination. Proceedings (Baylor University. Medical Center), 18(1), 21–25. https://doi.org/10.1080/08998280.2005.11928028
Rowe, J. H. (2006). THE INCA CIVIL WAR AND THE ESTABLISHMENT OF SPANISH POWER IN PERU. Ñawpa Pacha, 28(1), 1–9. https://doi.org/10.1179/naw.2006.28.1.002
Shuker, R. (2016). Beyond Texts: Notions Of Warfare In Inca Society. Tropos Journal, No. 39 (Spring 2016).