The History of Yatzy
A dice game whose scoring categories - pairs, three and four of a kind, a full house, a straight - read like a hand of poker, because that's exactly where they came from.
From Poker Dice to Yacht
Long before Yatzy, 19th-century "poker dice" games used five dice marked with playing-card faces (Nine through Ace) to deal out poker-style hands - pairs, three or four of a kind, a full house - without any cards at all. A later game called "Yacht", played with ordinary numbered dice and multiple rerolls per turn, adapted that same set of poker hand categories onto a numbered scoresheet, adding a straight and a five-of-a-kind of its own.
According to Hasbro, a Canadian couple whose names are not known played the game with friends aboard their yacht and called it "The Yacht Game". They asked the American toy maker Edwin S. Lowe to make sets of the game as gifts for their friends. Lowe saw a chance to sell it and acquired the rights from the couple in exchange for making 1,000 gift sets.
The Milton Bradley Years
E.S. Lowe acquired the rights and began manufacturing the game under a new trademarked name, "Yahtzee", starting in 1956. It became one of the best-selling dice games of the 20th century, and the E.S. Lowe Company itself was acquired in 1973 by Milton Bradley, which later became part of Hasbro - the company that still owns the Yahtzee trademark today.
Because "Yahtzee" is a registered trademark, other publishers and regions that wanted to sell or describe the same style of game generally couldn't use that exact name - one reason equivalent scoresheets circulated for decades under a variety of local names.
A Scandinavian Variant, and a Different Scoresheet
"Yatzy" is the name this style of game is generally known by across Scandinavia, and it plays with a couple of real rule differences rather than just a different label: the Nordic scoresheet adds two extra categories, One Pair and Two Pairs, that the standard American Yahtzee sheet doesn't have, for 15 categories and 15 rounds instead of 13.
The upper-section bonus differs too: American Yahtzee awards 35 points for reaching 63 or more in the Ones-through-Sixes section, while the Scandinavian Yatzy scoresheet used here awards 50 points for the same 63-point threshold - a small but genuine difference in the ruleset, not just a regional nickname for the identical game.
A Note on the Names
Yahtzee and Kniffel are registered trademarks. PaperGames is not affiliated with the owners of these trademarks and offers the Scandinavian version, Yatzy, which has its own rules for the straights.