Diogo is a Portuguese male name. Originally, this name comes from James which in turn is derived from the HebrewYaʻăqōbh (Jacob), via the name of Saint James the Great, to Santo Iago (or Sant'Iago), re-analysed as Santiago. The assimilation of the final t of Sant into the name is attested in other saints' names, including Spanish and Portuguese Telmo 'Elmo' (< Sant Elmo) and Slovenian Tilen 'Giles' (< Šent Ilen). Other ancient variations: Diogenes (Greek), Didaskein (Greek/Latin) and Didacus (Latin). In 2012 it was the ninth most common male name in Portugal and the forty-seventh most common male name in Brazil, where its Spanish version, Diego, is also very popular.