Hermenegildo González or Mendo I Gonçalves was a count in the 10th century Kingdom of León, and husband of Mumadona Dias, Countess of Portugal. He was son of count Gonzalo Betótez and Teresa Eriz, and maternal grandson of count Ero Fernández. His sister Aragonta González had been wife of Ordoño II of León before being set aside. Hermenegildo begins to appear in documentation in 926, and apparently died relatively young, as he is no longer seen after 943 (and was dead by 950), while his widow continues to appear through 981. His eldest son was count Gonzalo Menéndez, who first appears in a document of 24 July 950, the same document which confirms Hermenegildo as already dead. His other son, Ramiro Menéndez, may have fathered Velasquita, queen of Vermudo II of León.[1]