“By 1470, French card makers in Rouen had settled on the four suits we’re familiar with today. The church was represented by hearts, the state by spades, merchants by diamonds, farmers by clubs (which resembled more and more the clower they harvested). Earlier cards had been expensively hand-painted for the actual king and his court, but widespread demand among common folk soon led to mass production of uniform decks using woodcuts and stencils. Rouennais designers fashioned their court cards after historical figures. The king of spades was drawn to resemble David, king of the Hebrews, his sword modeled after the weapon he took from Goliath upon slaying the giant with a leather slingshot, which was shown lower down on his card. The club king depicted a stylized Charlemagne, the king of diamonds Julius Caesar, the heart king Alexander the Great. The four kings thus represent the Jewish world, the Holy Roman Empire, Rome, and Greece, the four main wellsprings of Western civilization. . . .

By the nineteenth century, as standard playing cards became double-ended, designers had to jettison the heraldry on the lower halves of the court cards. David’s slingshot disappeared, making his kingship more generic. Two images that survive are the orb of Christendom cupped in the left hand of the club king, and the three-belled flower, emblematic of the Holy Trinity, held by his queen.”

—James McManus, from Positively Fifth Street, 2003.