Sylvanus Morley, American archaeologist and scholar (d. 1948)
Sylvanus Griswold Morley (June 7, 1883 – September 2, 1948) was an American archaeologist and epigrapher who studied the pre-Columbian Maya civilization in the early 20th century. Morley led extensive excavations of the Maya site of Chichen Itza on behalf of the Carnegie Institution and published several large compilations and treatises on Maya hieroglyphic writing. He also wrote popular accounts on the Maya for a general audience.

To his contemporaries, "Vay" Morley was one of the leading Mesoamerican archaeologists of his day. Although more recent developments in the field have resulted in a re-evaluation of his theories and works, his publications, particularly on calendric inscriptions, are still cited. In his role as director of various projects sponsored by the Carnegie Institution, he oversaw and encouraged many others who later established notable careers in their own right. His commitment and enthusiasm for Maya studies helped inspire the necessary sponsorship for projects that would ultimately reveal much about ancient Maya civilization.

Morley also conducted espionage in Mexico on behalf of the United States during World War I, but the scope of those activities only came to light well after his death. His archaeological field work in Mexico and Central America provided suitable cover for his work for the United States' Office of Naval Intelligence. investigating German activities and anti-American activity.