The origin of blackjack is more obscure than that of any other online casino game. It has been traced to European gambling games that had similarities and differences with the modern game.

The earliest reference is from the early 17th century to a Spanish card game Ventiuna, the Spanish for 21. The major difference between Ventiuna and blackjack was that the decks did not have eights, nines and tens. The similarities were that players had to reach a total of 21 points without busting and that the ace could take values 1 or 11. Later the French played this game with slightly different rules. Their game was called Vingt et Un, which again is 21. In this game the dealer was allowed to double and players could bet after each round. Some card historians also include an Italian game referred to as Seven and a Half. This game was played with the face cards, the sevens, eights and nines. Players had to make a hand of seven and a half points. The sevens, eights and nines were valued at one point, while the face cards were valued at a half a point. Players busted if they went over seven and a half points. The king of diamonds was a wild card.

The French took Vingt et Un to North America after the French Revolution. The game evolved to its present form in the casinos of the United States. At first the game was not very popular. Therefore casinos offered bonus payouts to attract players. One bonus offered a 10 to 1 payout if the player was dealt the ace of spades and a black jack as the first two cards. This hand was called a blackjack. Once American players took to the game this bonus was reduced to a 3 to 2 payout for a hand with any ace and any card of face value ten. However, this hand continued to be referred to as blackjack and ultimately gave the game its name.

The history of blackjack in the United States from the middle of the twentieth century is very exciting and well documented. In 1956 Roger Baldwin published the first strategy manual for blackjack. In 1962 Edward Thorp published his card counting theory. Players kept track of the cards that were removed from the shoe and hence were better informed about the cards remaining in play. Thus they could take decisions to their advantage. Thorp’s book Beat the Dealer was on the New York Times best sellers list and did much to publicize the game of blackjack. However, players soon realized that card counting was not an easy practice.

Ken Uston took to card counting with a team and used mini computers hidden in their shoes. He made a lot of money this way in the 1970s. There are claims that the amount was upward of $300,000. The casinos went to court and got the use of mechanical devices by players outlawed and this put an end to card counting for a while. In 1980 Bill Kaplan formed a team of MIT students and evolved a highly sophisticated method of card counting. This team, which became known as the MIT Blackjack Team, operated profitably through the 1980s and 1990s. Then the casinos introduced measures like mechanical shufflers and discarding shoes with only half the cards dealt. This reduced the advantage of card counting to such an extent that it eventually died out.