Knapp was an illustrator. The original deck was published under his name only, and usually referred to as the Knapp Tarot. The title on the front of the box reads: Tarot, Revised Cards, New Art and Copyright, 1929, by J A Knapp, Los Angeles, Calif. However, it is assumed that even this original deck was a collaboration with Manley P. Hall and, in fact, later revisions and reproductions were sold as the Knapp-Hall Tarot. Prior to this deck, Knapp had provided illustrations for at least two of Hall's books. Hall was a prolific speaker and writer on all things esoteric and metaphysical, having authored over 200 books. Carl Jung was supposed to have been influenced by Hall in his exploration of psychology and alchemy during his later career.
This deck builds on the tradition of occultist tarot decks and can be seen as something like the apex of that trend that started in the 18th century. The images are reminiscent of the Rider-Waite deck but are different in both style and detail. This deck combines symbolism from ancient egypt, Cabbala, alchemy, astrology and other systems as was common in occult decks. It adds a unique element of "mandalas" which here appear as small schematic symbols on the face of each card which the reader is instructed to meditate on to develop their own intuitive insights. Although this concept comes from a Buddhist tradition, the symbols themselves are not Buddhist.
The deck is quite unique. The colors are beautiful chomolithographic which was state-of-the art printing at that time. The original deck is full of vibrant purples that for some reason were printed as black in the reproduction version from the 1970's. In general, the colors of the original are more subtle and inviting than the coloration in the reprint version which tends to appear gaudy and flat by comparison. The artwork is finely detailed and reminds me of the old Prince Valiant comics. The subjects build on the Rider-Waite tradition but are stylistically unique and include elements of Art Deco which characterized the era.
This deck is quite hard to find and is a much desired collectors item. Even the reproduction version has been long out of print.
I have one Knapp Tarot deck in my collection. It is in excellent condition. All the cards are present along with the original two-part purple box with gold lettering. There are no creases, tears, or other damage. The gold print on the box is somewhat faded. The cards have some yellowing typical of paper of this age, with the discoloration being more prominent near the edges. There are several small brown blemishes on just a few of cards (see pic). I believe (but can't say with certainty) that these are production defects and not damage. The original booklet is missing.
Go to the Knapp Tarot on Amazon.com: Knapp Tarot