Celtic Mythology is the mythos and legends of Celtic polytheism, the religion of the Iron Age Celts. Early Celts maintained a polytheistic mythology and religious structure, but after the Roman Empire invaded almost all Celtic people were converted to Christianity and the majority of the Celtic Mythology and language was lost to antiquity. Names from Celtic Mythology are primarily the names of gods, demi-gods and heroes featured in the stories and legends passed down among the Celtic communities and ethnic groups around the British Isles. As such there may be commonalities between Celtic, Gaelic, Brythonic, Welsh, Irish and Scottish names and name meanings as they all have a common ancestral language tree. Baby Name World has many baby names and name meanings from all these diverse categories to make choosing a name easier for you.