Several years ago, I got a tattoo on my forearm, and a lot of people ask me about it. It shows an iconic castle, a fish, and the letters “HR.” The fish represents Jesus Christ, and the letters stand for “Holy Rood,” the medieval term for the cross. The castle represents the Grail Castle, the resting place of the mythical Holy Grail.

I initially came across the image when I was doing research for my novel Zen, Mississippi, begun around 1992 and finished just recently (still unpublished, unfortunately).

The metaphor of the grail quest, borrowed from the legends of King Arthur, plays a major role in that story. The book where I found the image (The Holy Grail by Norma Lorre Goodrich” only said that it was a “medieval water-mark on paper” and that it represented the Grail Castle.

For years, that was basically all I knew about the image. I got it tattooed on my arm for all kinds of reasons, none of them particularly religious in nature. The image struck a chord with me mainly because of my identification and fascination with the knights-errant who search for the grail. It just so happens that the symbolism of Arthurian legend is intricately tied in with the symbolism of Christianity. Also, I liked having a tattoo that tied in with the novel I’d then been working on for several years (and would continue to work on for several years after that), and I just liked the way it looked—castles are cool; most people I think would agree.

Just this week, I happened upon some more information. It turns out that the image originated with one of the most infamous heresies of the Middle Ages, the Cathars who lived in the South of France in the 12th and 13th centuries. The Cathars were a Gnostic sect who believed the Catholic church had corrupted the original message of Christianity. They were also vegetarians and possibly sodomites. Many of them were massacred by the Church in the early 13th century.

Enthusiasts of the DaVinci Code and its “nonfiction” predecessor Holy Grail, Holy Blood may be familiar with the Cathars as the Gnostic sect that evolves into the Priory of Sion, the group at the heart of the grail conspiracy, according to those books.

Conspiracy or not, the Cathars did use a lot of Arthurian imagery in their symbols, and they put these symbols in all kinds of places—tapestries, pottery, etc—trying to spread the word about their beliefs. Many of the Cathars were also some of the earliest manufacturers of paper, and that’s why Cathari symbols were often used as watermarks during that time. The Cathar watermarks were also precursors to the images associated with the Tarot.

In full disclosure, I have not read the DaVinci Code (or seen the film), and I don’t particularly care to. And I’m not a believer in that particular conspiracy. I also can’t say I share many of the Cathars’ specific beliefs—or even understand them. But I do like the fact that I can now identify my tattoo with an interesting and esoteric historical event, and like the search for the grail, my search for information about this image continues.

More will be revealed.