Historians disagree. This table summarises the main arguments:
| Factor | Argument FOR it being decisive | Argument AGAINST |
|---|---|---|
| Disease (smallpox) | Killed 40% of Tenochtitlan before the final siege; killed the emperor; devastated defenders' capacity to resist | Disease alone did not create Spanish victory — it still required military action and political organisation |
| Indigenous alliances | 200,000 Tlaxcalan warriors dwarfed Spanish numbers; they conducted most of the actual fighting | Alliances were partly enabled by Spanish military technology and by distrust of Aztec rule — not an independent factor |
| Spanish military technology | Horses, steel, cannon caused psychological and tactical shock; Aztec warriors could not match armoured cavalry | Technology alone did not win the war (La Noche Triste showed Spanish could be defeated); indigenous numbers were the real military force |
| Cortés's leadership and diplomacy | His strategic decisions — alliances, taking Moctezuma hostage, building brigantines — were crucial at every turning point | One man's decisions were made possible by structural factors (disease, political fragility) he could not have manufactured |
This comparison covers ⚖️ Which Factor Was Most Important? within Aztecs and the Spanish Conquest, 1519-1535 for GCSE History. Revise Aztecs and the Spanish Conquest, 1519-1535 in Component Group 5 — World Depth Studies for GCSE History with 14 exam-style questions and 17 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 8 of 14 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Aztecs and the Spanish Conquest, 1519-1535
Describe two features of the Aztec Empire in 1519.
Describe two features of Hernán Cortés's expedition to Mexico in 1519.
Quick recall flashcards
Describe Cortés's expedition to Mexico in 1519.
Cortés landed in February 1519 with approximately 500 soldiers, 16 horses, and cannon. He had defied the governor of Cuba (Velázquez) who tried to cancel the expedition. He famously scuttled (or beached) his ships to prevent his men deserting, cutting off retreat and forcing commitment to the conquest.
What was La Noche Triste and what happened?
The 'Night of Sorrows' (30 June–1 July 1520). While Cortés was away, Aztec warriors rose against the Spanish garrison; Moctezuma II was killed (by Spanish or his own people — disputed). The Spanish fled in chaos across the causeways, with hundreds drowning weighed down by stolen gold. It was a major Spanish defeat.