Gaila (Basque): Feminine form of Gailo.
Gaitelgrima (Italian): Also an Ancient Germanic–Lombardic name.
Galiana (Italian, German): Feminine form of Galian. The Medieval Occitan form was Galiane.
Gazte (Basque): “Young.”
Gerwara (Danish): Either a form of unisex name Gerwar or a feminine form of Ancient Scandinavian name Gæirvarr. When Gerwar was used on a girl, it was a form of Ancient Scandinavian name Gæirvǫr (from roots geirr [spear] and vár [woman, spring]). On a boy, it was a form of Gæirvarr (from roots geirr and varr [wise; alert, shy, attentive).
Ghisolabella (Italian): Combination of Ghisola and bella (beautiful). Ghisola was a form of Ancient Germanic name Gisila, whose modern form is the familiar Giselle). It derives from the word gisil (pledge, hostage). I completely fell in love with this name when I discovered it in The Divine Comedy.
Girolama (Italian): Feminine form of Jerome, which derives from Greek name Hieronymus (sacred name). Its roots are hieros and onoma.
Gordislava (Russian, Slavic)
Gostansa (Catalan): Probably a form of Constance.
Galeazzo (Italian): Form of Galahad, via alternate form Galeas.
Galfrido (Italian): Form of Medieval Tuscan name Gualfredo, which derives from Ancient Germanic names Walahfrid and Walfrid. The roots of the former are the Ancient Germanic walha (stranger) and frid (peace), while the roots of the latter are the Gothic valdan (to reign) and Old High German fridu (peace).
Galib (Moorish Arabic): “Victor, winner.” The feminine form was Galiba.
Gangalando (Italian): Derived from an Ancient Germanic name with roots gang (path) and land (same meaning in English).
Garnier (French): Form of Werner, which derives from Ancient Germanic roots warin (guard) and hari (army).
Garsea (Spanish): Possibly derived from the Basque word hartz (bear).
Gatbay (Judeo–Catalan): Form of Hebrew name Gabbai, which possibly means “to dig.” In Aramaic, the word gabbai refers to a tax-collector, treasurer, or charity-collector.
Gelfrat (German): From High German roots gelf (boast, yelp) and rat (advice, counsel).
Giuscard (Norman French): Form of Norman name Wischard, which derives from Old Norse roots viskr (wise) and hórðr (brave, hardy).
Glockrian, Glogryan (German): Form of Kalogreant, which derives from Arthurian name Calogrenant.
Glúniairn (Irish, Scandinavian): “Iron-kneed.”
Gostislav (Slavic): “Guest’s glory,” from roots gosti and slava.
Guildhelm (Dutch): Form of William, which derives from Ancient Germanic name Willahelm (roots wil [desire, will] and helm [helmet, protection]).