Augustus Le Plongeon (1826–1908) was a French-American archaeologist, photographer, and antiquarian whose work focused on the pre-Columbian civilizations of Mesoamerica, most notably the Maya civilization. A controversial figure in his time, Le Plongeon was one of the earliest proponents of the idea that the Maya civilization was much older than widely accepted and claimed that it had influenced the ancient cultures of Egypt and Atlantis. He conducted extensive fieldwork in the Yucatán Peninsula, documenting Maya ruins with pioneering use of photography and engaging in excavations. His scholarly pursuits culminated in writings such as 'Sacred Mysteries: Mayas & Kʼicheʼs,' wherein he explored the religious and mythological aspects of the Mesoamerican cultures. Le Plongeon's theories and methodologies were often disputed by his contemporaries, and much of his archaeological interpretations have since been debunked by modern scholarship. Despite this, his documentation of Maya ruins remains a valuable record of the sites during the 19th century. His literary style tends to blend his speculative theories with his archaeological observations, making his work a curious amalgamation of science and pseudoscience. His legacy, although marred by his less rigorous scholarly standards, continues to be of interest to historians of archaeology who study the development of Mesoamerican archaeology and its early figures.