The nopal, or prickly pear cactus, is a common cactus native to Mexico and the American Southwest. This cactus holds great cultural significance to the people of Mexico and is featured on the Mexican flag as an homage to the story of how Tenochtitlan, in today’s Mexico City, became the capital of the Aztec Empire. The Aztecs, one of several indigenous Nahua groups of Central Mexico, have a rich tradition of oral and glyphic history, recorded in documents often referred to as codices. The Florentine Codex, a series of 12 books, meticulously documents the lives of the Nahua people and is written by Nahua authors and Spanish translators. By analyzing the textual and visual representations of the nopal in these books, I seek to understand the many roles that this essential plant played in the lives of the indigenous Nahua prior to and during Spanish colonization. By looking at the nopal’s role as food, medicine, cultural and geographical symbol, and host for the parasitic and prized cochineal, I seek to foster greater understanding of the nopal’s significance to the ancient Nahua people, and how their descendants have carried some of this knowledge into the modern world.