|On the night of July 1, 1520, Cortez's army left their compound and headed west, toward the Tlacopan causeway. The Spaniards made their way out of their complex unnoticed but were seen by Aztec warriors known as the Eagle Warriors, who sounded the alarm. The fighting was ferocious. |
As the Spaniards and their native allies reached the causeway, hundreds of canoes appeared in the waters. Weighed down by gold and equipment, many soldiers lost their footing, fell into the lake, and drowned. Sources vary as to the total number of casualties. It is thought at least 450 Spaniards died and 4,000 of their allies.