Celtic God, Worship of him was widespread to Romania and Italy.
The Lord of the Wild Wood and often seen as -if you follow this belief- is the lover of the Goddess -Mother Earth or Gaia- and is often depicted as Herne the Hunter and being brother to the Green Man.
Cernunnos, being the Lord of the Wood, is known to have stag antlers, but is closely compared to Pan, Dis Pater -or so said Julius Ceasar- due to his appearance. He is also shown having a snake in one hand and a sacred torc in the other. This is very famous as it is shown on the Gundestrup Cauldron.
Cernunnos in Latin means "The Horned One", which is another way of referring to him.
A cave painting in France shows a tall man figure with antlers.