Blackjack originated in the 17th century as "Vingt-et-Un" in France and evolved into its current form in the United States during the 19th century, gaining popularity under its new name and the introduction of specific bonus payouts. The game's popularity surged in Las Vegas during the mid-20th century as casinos effectively promoted it with favorable rules. The 1960s saw the emergence of card counting techniques, adding a strategic element that attracted skilled players. With the relaxation of gambling laws and the advent of online gaming in the late 1990s, Blackjack expanded its reach and continues to be a staple in both physical and digital casinos, maintaining its status as one of the most popular casino games.