My most famous historical namesake is one Cosmas Indicopleustes, a sixth century merchant from Alexandria who traveled to southern India (hence his name) and other ports on the Indian Ocean, only to return home to Egypt, become a monk, and write a book denouncing the idea of a spherical Earth as pagan nonsense. I am happy to report that his Christian Topography is now online. The good people at tertullian.org have added a preface saying that learned Christians didn't buy it, and anyway Cosmas was some kind of Nestorian so he doesn't count.