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The Triple Alliance was an elected monarchy chosen by the elite. The emperors of Tenochtitlan and Texcoco were nominally equals, each receiving two-fifths of tribute from the vassal kingdoms, whereas the emperor of Tlacopan was a junior member and only received one-fifth of the tribute,[citation needed] due to the fact that Tlacopan was a newcomer to the alliance. Despite the nominal equality, Tenochtitlan eventually assumed a de facto dominant role in the Empire, to the point that even the emperors of Tlacopan and Texcoco would acknowledge Tenochtitlan's effective supremacy. Spanish conquistador Hernán Cortés executed Emperor Cuauhtémoc and installed puppet rulers who became vassals for Spain.