What I Think I Know About Early Playing Cards

Bearing in mind that I'm probably completely wrong about some of this:

I think playing cards originated in China and were transmitted through the Middle East to Europe.
-Some of the earliest Italian references to the game refer to it as being a Saracen game and use some variation of the word na'ib to reference the game.
-But there are no instances of cards in India, that I am aware of, during the period when cards would have passed through from China to the Middle East.  Cards could have skipped India but I consider this less likely.
-I have looked for references to playing cards in Islamic literature of the time and haven't found any.  I would expect a game that is mostly chance to be very firmly denounced by religious scholars of the time and I don't see anything.  Since I've barely scratched the surface of the material relating to the medieval Islamic world it could simply be that I haven't yet found one of many, potential, references.
-The earliest cards to survive in the Middle East are the Topkapi deck(s) from the 15th-16th Century.  This is well after playing cards are documented in Europe.
-The De Unger card fragment predates all cards by a considerable time frame IF it's actually a playing card fragment (I believe it is) AND the dating is correct (I'm skeptical but I'm not a world class authority on Islamic art).

Playing Cards entered Europe through Spain and Italy at about the same time.
-Sometime just before or in the last quarter of the 14th Century.
-If I had to guess I'd say they entered Italy first.
-Diffusion was incredibly rapid in some areas.  In Paris they're outlawing card-play on work days by 1380.  Yet cards seem to have avoided England for another couple of decades.

The earliest playing cards were hand drawn/painted.
-The earliest references to playing card manufacturers are people who were also artists.
-Many of the earliest decks (Cloisters, Topkapi) are hand drawn/painted.
-But the fact that cards were available to enough of the working class in 1380 Paris to draw legislation that forbid playing on work days suggests that cards were cheap and plentiful and, thus, not confined to expensive and rare works of art.

Playing cards were probably one of the earliest mass-manufactured items using block printing.
-Which is curious because block printing had been around for a while.  It was used in Europe for printing fabric and images of Saints and in the Islamic world for fabric and 'magic' amulets.  But printing on paper doesn't become a big thing until the 15th Century.
-Cards tended to be printed using woodblocks.  Once printed they were colored, to some degree or another, using stencils, hand-painting, and in the case of at least one deck by finger-painting.  I am not aware of any decks of cards that were not colored in some way.
-Red, Yellow, Green, Blue, and Purple seem to have been the primary colors used in stenciled decks.  Painted decks used the full-spectrum of colors.  The Topkapi deck(s) may have used a couple varieties of gold leaf (adulterated with silver).
-Stencils were not particularly detailed and the paint went over the printed (black) lines and was sometimes off-center.
-It was difficult for printers to produce a uniform card back.  This did not prevent them from trying.  So while plain backs and mono-color backs were the most popular options early on there are illustrations from quite early showing cards with decorated backs.  Diapered patterns (look it up) seem to have been very popular and card makers may have counted on each card being different enough, and similar enough, that individual cards could not be made out from their back alone.  This was a technique used in the 18th Century where card makers printed cards with complicated, but individual patterns.
-Cards started off with a single orientation that showed the whole figure of court cards rather than the double-ended, half-figure cards we are used to today.
-Cards lacked corner indices to indicate the value/order of the card and the suit of the card.  These were added (number/value first) beginning in the 17th Century.
-Cards were printed on large sheets which were then cut with large scissors to make a finished deck with square corners.  In general.  There are also examples of cards with non-rectangular shapes.  The Cloisters cards are oval.  Der Meister der Spielkarten made a 15th Century deck that was round.  Some early decks clearly have rounded corners.
-Many (most) of the surviving examples of cards we currently have are printer's cast-offs.  Sheets that were not used for one reason or another and were re-cycled to be put to other uses in the print shop.

The paper used to produce playing cards was of a good quality.
-Primarily hemp with linen, hair, and other fiber add ins.
-It seems to have been a pretty durable paper.
-Cards seem to have been printed on paper in which the glue (a starch glue made from wheat flour and water) played a significant role.  Multiple sheets seem to have been glued together to form a pasteboard.  Later illustrations (wood cuts) will show printed sheets of paper hanging over wood rods to air dry.  Putting these together and getting the requisite stiffness suggests the glue was important and that paper was made thick after printing rather than before.  We know from later accounts that paper was definitely glued together before printing so perhaps the printed veneer sheet was glued to a paste-board sheet?  The truth is that variety ruled.  Playing cards made on cardstock (a thick single layer of paper) have been found as have cards made from putting together layers of paper.
-The references to playing cards being fined with chalk and starch appear to refer to the single example of the Cloisters playing cards which were prepared in the fashion of a typical painting by having at least one layer of gesso (starch and chalk) applied.  This made the playing cards quite thick and produces an effect not seen in other decks of cards so it's likely this was atypical.  The Stuttgart deck was also fined with gesso.

Regional card styles were in place before the middle of the 15th Century.  Major design schools include:
-Islamic.
-Latin (Italian and Spanish).
-German (Swiss, German).
-French.
-There were blended forms in the geographic areas between the major regional areas.  E.G. there are decks showing combinations of Italian and German elements in the area between Switzerland and Northern Italy.
-As cities became established production centers for playing cards they produced decks for export.  So you can find Spanish-style decks being produced in Germany.  Or Italian decks being produced in France.

The Islamic Style includes:
-A court composed of a king, a deputy, and an under deputy.  The courts are represented by a simple throne and do not have any animals or people depicted.
-The suits are coins, cups, swords (primarily curved with straight swords for the odd numbered cards, less the ace), and polo-sticks.
-Floral decoration plays an enormous role.
-The Topkapi deck is the primary example of this style and is actually a deck comprised of a major contributor deck that has been supplemented with cards from at least one, and possibly two, other decks.  The cards are enormous (8 inches high) and each one appears to have been hand made.  They were also modified by the addition of the blue fields with Arabic script.

The Latin Style includes:
-A court composed of a king, knight, and page.  The courts are represented by human figures.  The king is typically seated, the knight is typically mounted.
-The suits are coins, cups (the Spanish style cup is more square/blocky), clubs/batons (the Spanish style club is a crude cudgel that might still have some leaves on it while the Italian style baton is a crafted symbol of position rather than a crude club), and swords (Italian swords are curved except for the ace and, usually, the odd sword on odd numbered cards, Spanish swords are straight, except for, usually, the ace).
-The arrangements of the suit cards are fairly standard within the two styles and the Spanish arrangement is different from the Italian.
-The later you go the more pip cards the Spanish deck does away with.  While it starts out with 10's it quickly discards those.  In some later decks the 9's are also discarded.

The German Style includes:
-A court composed of a king, over, and under.  The courts are represented by human figures.  The king is typically seated, the over and under stand.  The over is designated by the suit sign being at head level or higher.  The under is designated by the suit sign being a foot level.  There are examples of mounted overs by they are not frequent.  There are also examples of decks with a king, mounted knight, over, and under.  There are also decks with queens.  In fact, you can find just about any court composition in German decks if you look long enough.
-The suits are typically hearts, leaves, bells, and acorns for German decks.  Swiss decks typically use shields, leaves, bells, and acorns.  HOWEVER, the Germans put just about anything on a deck.  Hunting themes were popular but you can find birds, dogs, crowns, the heads of priests, and lots of other items being used for suits.  I have counted more than thirty different suits in use in the various examples of German/Swiss decks.
-German style decks typically use a ten with a Roman numeral ten on them (X).  Swiss decks typically use a banner displaying the suit symbol for the ten. You can find instances of both in both (i.e. German decks with banner tens and Swiss decks with X tens).
-Neither deck typically uses an ace (1) card.

The French Style includes:
-A court composed of a king, queen, and jack.  The courts are represented by human figures,  The king may be seated (in earlier decks) or standing (particularly in later decks) and is typically distinguished by a crown and a robe that reaches the floor.  The queen may be seated or standing.  The jack is typically standing and has short robes.
-The suits are hearts, diamonds, clubs, and spades though the shapes are called differently in French.
-The French suits were adopted by the English and became the standard international deck we know today.
-Some French decks appear to have had a court composed of two kings and two queens and one jack.
-At least one French deck was made with five suits with the fifth suit being a red crescent.