Alex Casteel is an archaeologist, art and architectural historian, and specialist of the northern Middle Ages. He is a PhD candidate in the Cotsen Institute of Archaeology at the University of California, Los Angeles (UCLA).

Alex's dissertation explores the unprecedented 9th- to 11th-century global circumnavigation across the North Atlantic through architecture, material, and art. He examines the exchange, evolution, form, and meaning of maritime and terrestrial construction, of earthen building, and of architectural objects. Alex locates the confluences of Indigenous Arctic-American, European, and Scandinavian-Viking practices, offering a counternarrative to canonical histories of the Middle Ages rooted in the hegemony of Christian, European, and Latinate peoples.

He has received funding from the Smithsonian Institution, the Leifur Eiríksson Foundation, the Vernacular Architecture Forum, and the Danish American Heritage Society, as well as UCLA's Center for Medieval, Renaissance, and Early Global Studies, Center for European and Russian Studies, Department of Art History, and Cotsen Institute.

Alex leads the Digital Turf Project, a digital humanities initiative rooted in Icelandic fieldwork that seeks to improve global understanding of earthen building. He is also working on the Viking Transatlantic Project, a database of early longhouses and churches excavated in the North Atlantic from Orkney to Newfoundland.