A professor of religion at the University of Southern Mississippi, Slagle’s 2011 study, The Eastern Church in the Spiritual Marketplace: American Conversion to Orthodox Christianity, was one of the first studies to focus specifically on American conversions to Eastern Orthodoxy, an area of research that would soon be followed by Oliver Herbel (2014), Turning to Tradition, and Sarah Riccardi-Schwarz (2022), Between Heaven and Russia.