Complex sentence: The fall of the Aztec Empire was the key event in the formation of the Spanish overseas empire, with New Spain, which later became Mexico, a manor component and the rest of the Aztecs were kicked out by the Spanish.
Split into simpler sentences: The fall of the Aztec Empire was the key event in the formation of the Spanish overseas empire, with New Spain, which later became Mexico, a manor component. The rest of the Aztecs were kicked out by the Spanish.