This name was also borne by a powerful 10th-century ruler of Bulgaria who expanded the empire to its greatest extent.
A city in Italy bears this name, though in this case it originates from Latin Mediolanum, perhaps ultimately of Celtic origin meaning "middle of the plain". In some cases the city name may be an influence on the use of the given name.
Other famous bearers of this name include Spanish painter Diego Velázquez (1599-1660), Mexican muralist Diego Rivera (1886-1957) and Argentine soccer player Diego Maradona (1960-2020).
Other notable bearers of the name include the Russian emperor Boris Godunov (1552-1605), later the subject of a play of that name by Aleksandr Pushkin, as well as the Russian author Boris Pasternak (1890-1960), the Bulgarian king Boris III (1894-1943), and the Russian president Boris Yeltsin (1931-2007).