The image, found carved into corbels and roof bosses in churches and cathedrals across the land, is such an overtly pagan one that nobody really knows why the Green Man is so prominent in Christian art. There seems to be four main types of Green Man: the spewing head, where the leaves emerge from the mouth, the foliate head where the leaves and face merge into one another, the "bloodsucker" where the leaves emerge from the eyes, nostrils and mouth and the Jack in the Green, a face surrounded by a halo of leaves.

There is the possibility that the Green Man may be linked to the figure found in English folk tales, Jack in the Green. This folk figure is hundreds of years old, dating back to the days when people worshipped the old Gods and Goddesses. In a fertility ritual, performed on May Day or Beltane, (which was revived in Victorian times) Jack in the Green, a man dressed in a frame of greenery, was led in procession around the village, ending with the symbolic death of the Jack. He is mentioned in the ancient Morris dance song, "Jack on the green," a contortion of Jack in the Green.