More info about the name "Guilherme"
Guilherme is a Portuguese variant of William. William originates in Germanic languages and means "strong mind and protection". It became a popular masculine given name in England after William the Conqueror was recognized as the first Norman king of England. Since then, the name has been extremely popular within royalty, borne by various kings and rulers. In the United States its popularity dropped in the 1970s, but started gaining it back in the new millennium and is currently one of parents’ most favorite boy’s names.