The Rise of the Inca Empire

The rise of the Inca Empire describes the process by which a small highland kingdom centered on the city of Cusco in what is now southern Peru was transformed, in fewer than five generations, into the largest empire of the pre-Columbian Americas. The transformation is conventionally dated from the reign of the emperor Pachacuti Inca Yupanqui (r. c. 1438–1471), who is credited with reforming the Inca religion, reorganizing the state, and launching the wars of conquest that carried the Inca armies north into present-day Ecuador and south into Chile. The process continued under his son Túpac Inca Yupanqui (r. c. 1471–1493) and his grandson Huayna Capac (r. c. 1493–1527), each of whom added vast new territories to the empire. The detailed story of Pachacuti’s reforms is told in the article on Pachacuti and the reorganization of the Inca state, while the principal military campaigns are surveyed in top Inca military campaigns, and the combination of war and diplomacy in the expansion is examined in conquest and diplomacy in Inca expansion.

The imperial transformation was, in the most literal sense, a revolution. Within the lifetime of a single ruler, the Inca went from being one of dozens of small polities competing for survival in the central Andes to being the rulers of a state of more than a million square kilometers. The process is unintelligible without the Andean context described in the overview of the origins and founding of the Inca, and it set the stage for the further development described in the Inca Empire at its height. For the broader narrative of which the rise of the empire is a part, see the general history of the Inca civilization.

The Chanka Crisis and the Accession of Pachacuti

The reign of the Inca ruler Viracocha (sometimes called Inca Viracocha, to distinguish him from the creator deity of the same name) is traditionally dated to the early fifteenth century. The chronicles describe a kingdom beset by drought, factionalism, and external pressure, especially from the Chanka, a powerful confederation of peoples in the Andahuaylas region of what is now Apurímac. Around 1438, the Chanka launched a major invasion of the Cusco valley, advancing on the capital itself. According to the most common account, the aged Viracocha and his designated heir Urco fled the city, abandoning it to the invaders. The young prince Cusi Yupanqui, son of Viracocha and brother of Urco, refused to follow. Rallying what remained of the Cusco army, the local ayllus, and reportedly allies from outside the valley, Cusi Yupanqui met the Chanka on the plain outside Cusco and decisively defeated them. He then assumed the royal title, taking the name Pachacuti — sometimes translated as “he who remakes the world” or “cataclysm” — and disinherited his brother Urco.

The traditional date of the Chanka victory is 1438, and the event is treated by the chronicles as the hinge of Inca history. Archaeology and historical linguistics provide some support for a real conquest of the Cusco valley in this period, but the details of the campaign — the tanpu battle, the role of the allies, the appearance of the sacred stones of the huacas — are clearly stylized. What is not in doubt is that within a generation of the supposed Chanka crisis, the Inca had become the dominant power of the central Andes. The pattern of rapid imperial expansion, religious reform, and large-scale forced resettlement that followed is examined in the article on Pachacuti and the reorganization of the Inca state.

The historical reality behind the Chanka crisis is debated, but the political consequences are clear. The Chanka war provided Pachacuti with a justifying narrative of national survival, a need to garrison the frontiers, and a client base of loyal ayllus rewarded for their participation. It also justified the disinheritance of Urco and the suppression of the older Hanan Cusco nobility, who were partly replaced by a new imperial elite. The result was a new kind of Inca state, organized around the cult of the Sun, the person of the emperor, and the project of imperial expansion.

The Reorganization of the Inca State

Pachacuti is credited with a sweeping reform of Inca institutions. Cusco was rebuilt as a ceremonial capital whose plan reflected the cosmological map of the empire. The great temple of Coricancha, the Temple of the Sun, was erected on the site of earlier shrines and decorated with sheets of gold. The city was divided into upper and lower halves, with the four great roads radiating to the four regions — Chinchasuyu to the north, Antisuyu to the east, Contisuyu to the west, and Collasuyu to the south — physically laid out as well as administratively constituted. The whole urban scheme was understood as a microcosm of the empire, and the architecture of Cusco of this period was a visible projection of the imperial order.

Pachacuti’s religious reforms are the most striking single feature of his reign. He is credited with elevating Inti, the Sun, to the supreme position in the Inca pantheon, demoting older creator gods such as Viracocha and Pachayachachic, and ordering the public worship of Inti at new state temples built throughout the empire. The cult of the Sun was tied to the dynasty: the Sapa Inca was the son of the Sun, and his authority was justified by a continuous relationship with the divine. The reform was not purely theological; it was also a means of binding recently conquered peoples to the new state, and it was accompanied by a project of forced resettlement in which whole populations were moved from their home regions to the fringes of the empire in order to break local loyalties and ensure the security of the new roads. The article on Pachacuti and the reorganization of the Inca state treats these reforms in greater detail, and the religious framework is set out in the article on the Inca pantheon.

A third great reform was the construction of the Qhapaq Ñan, the great royal road system, and the network of tambos (way stations) and qollqas (state storehouses) that made the new empire governable. The road system is described in detail in the article on the Inca road system; the storage system is treated in the article on qollqas and state storage. The roads served military, administrative, and religious purposes, and they made possible the rapid movement of armies, messengers, and mit’a laborers that the imperial project required.

Military Campaigns and the Imperial Army

The Inca army of the imperial period was organized on a decimal basis, with units of 10, 50, 100, 1,000, 5,000, and 10,000 men under appointed commanders. The basic tactical units were armed with slings, maces, spears, clubs, axes, and — among elite troops — copper and bronze weapons. Quipus were used to record the size of units, the tribute owed, and the campaigns undertaken. The army was supported by a logistical system of roads, tambos, and qollqas, and by a system of military colonies called mitma settlements, which moved loyal populations to strategic points across the empire. The article on top Inca military campaigns describes the principal engagements in detail, and the article on conquest and diplomacy in Inca expansion examines the political and economic arrangements that followed.

The earliest campaigns under Pachacuti are said to have been directed against the peoples of the central highlands: the Chanka themselves, the Quechuas of the Apurímac, and the Kichwa of the tropical lowlands. The first major extension came in the region of the southern altiplano, where the Inca moved into the territories of the Lupaca, Colla, and other Aymara-speaking peoples. The conquest of the altiplano, completed under Túpac Inca Yupanqui, brought the empire to the shores of Lake Titicaca and into contact with the Tiwanaku and Wari successor states of the region.

The second great wave of expansion was northward. Under Túpac Inca Yupanqui and Huayna Capac, Inca armies crossed the Vilcanota and Apurímac and pressed on into the northern highlands of present-day Peru and Ecuador. The most significant single campaign was the conquest of the kingdom of the Chimú on the north coast of Peru, a wealthy state whose capital at Chan Chan was the largest adobe city in the pre-Columbian world. The Chimú kingdom, although formidable, was defeated by a combination of military pressure, diplomatic isolation, and the exploitation of internal rivalries. Farther north, the Inca encountered the kingdom of Caranqui in the highlands of what is now Ecuador, and the chroniclers describe a bloody war of conquest there as well. The article on the size of the Inca Empire at its greatest extent maps the resulting territorial extent.

The third great theater was the southern frontier, where the Inca pushed into the Atacama desert, the Argentine northwest, and the forested slopes of the eastern Andes. The so-called Diaguita, Huarpe, and other peoples of the southern cone were incorporated through a mixture of warfare, marriage alliances, and the establishment of Inca garrisons. None of these distant regions was ever fully integrated into the imperial system, and the southern frontier remained a zone of intermittent warfare throughout the imperial period.

Conquest and Diplomacy

The expansion of the Inca Empire was not a uniform process of military conquest. The Incas, like other imperial powers, made extensive use of diplomacy, marriage alliance, and the threat of overwhelming force. In many cases, the first Inca envoys arrived before any army, and rulers who submitted voluntarily were typically confirmed in office as curacas, hereditary leaders bound to the Inca by oath and tribute. The most spectacular case is the kingdom of the Chincha on the central coast, whose ruling family was integrated into the Inca nobility through marriage. The article on conquest and diplomacy in Inca expansion examines the institutional and political machinery of this process in detail.

Where diplomacy failed, the Incas were prepared to use overwhelming force. The strategy of the imperial army combined pitched battles, sieges, and economic warfare, and it was supported by the resettlement policies of mitma and mit’a labor. The famous policy of forced relocation — mitmakuna — moved entire ethnic groups from one region to another, breaking up rebellious populations and providing loyal settlers for new conquests. Combined with the imposition of Quechua as a lingua franca and the relocation of sun temples and qollqas throughout the empire, the strategy of conquest was followed by a systematic effort at cultural and political assimilation. The article on the family and the ayllu sets out the kinship structures on which the policy relied, while the article on Inca social hierarchy explains the place of relocated populations in the imperial system.

The combination of military conquest and negotiated incorporation produced a remarkably durable empire. Most of the peoples of the central Andes had been absorbed into Tawantinsuyu by the time of Huayna Capac’s death in or around 1527, and the empire was governed by a system of provinces, road systems, and storage facilities that allowed the central government to project authority over an unprecedented area. The political consequences of that consolidation are examined in why the civil war weakened the empire before the Spanish arrival, and the long aftermath is described in the account of the last Incas.

Legacy of the Imperial Transformation

The transformation of the Inca state under Pachacuti and his successors was, in the end, a long-term political and cultural success. Within a hundred years, the Incas had built the largest and most populous state in the pre-Columbian Americas, sustained by a sophisticated system of administration, road communication, and labor mobilization. The institutional legacy of the transformation endured long after the Spanish conquest: the road system was used by the Spanish themselves as the basis of their colonial administration, the mit’a system was adapted to the needs of the colonial silver mines, and the Quechua language, spread by the Incas as a lingua franca, is still spoken by more than ten million people across the Andes.

The transformation was, however, incomplete. Many of the peoples incorporated into the empire retained their local languages, gods, and traditions, and the southern and eastern frontiers remained zones of rebellion and flight. The tensions produced by the imperial project were, in fact, central to the political crisis that broke out after the death of Huayna Capac, when the empire was torn apart by the civil war between Huáscar and Atahualpa. And the very institutions of the imperial state — roads, storage, and labor mobilization — would later be turned against the Incas by the Spanish, who captured and used the same system to consolidate their own rule. The article on the last Incas after the conquest describes the long aftermath of the imperial transformation in the form of the Neo-Inca State of Vilcabamba.