From Germanic

From a Germanic name meaning "power of the spear", from the elements ger meaning "spear" and walt meaning "power, authority". The Normans brought it to Britain. Though it died out in England during the Middle Ages, it remained common in Ireland. It was revived in the English-speaking world in 19th century.There were a few medieval French and German saints bearing this name. It was also borne by an 8th-century Anglo-Saxon saint. In this case his name may represent an Old English cognate of the continental Germanic name.