In 1878, Canadian player Cyrille Dion (sometimes referred to as "The Bismarck of Billiards" won the first pool (pocket billiards) Championship of America.

"Cyrille Dion (March 1843 October 2, 1878),[1] sometimes called "the Bismarck of Billiards", was a top player of both carom billiards and pool (pocket billiards) during his era. Hailing from Montreal, Dion was champion of Canada in 1865. He won the last American four-ball billiards championship, held in 1873. After three-ball billiards came into vogue, he won the world championship at straight rail in 1875, and three years later, the first Championship of America at pool in 1878. He died just six months later at age of 35.[2]" Source:

[First pool] Championship of America

The first Championship of America at pool took place in 1878 at the Union Square Billiard Rooms in New York City.[10] The game played was called fifteen-ball pool (sometimes called 61-pool), the rules of which are still listed in the Billiard Congress of America'sOfficial Rules and Record Book, despite being defunct for over 100 years. In it, the number of the ball pocketed by a player scores the player that number of points. The first player to rack up 61 or more points (being more than half of the total of all the ball numbers combined) wins a "frame". The championship was played on a race-to-21-frames format. Dion won the championship on April 20, 1878, beating out Gotthiel Wahlstrom of Sweden, 11 frames to 7. Dion won the title of Champion of America at pool, a gold medal and a cash prize.[11][12] Dion did not retain the title for long. He was challenged by Wahlstrom shortly after the tournament to a match for the title and lost.[1] Source:

61 Pool was played with a set of balls numbered 1 thru 15, same as today. If you add up the numbers of all 15 balls the total is 120 and so the first player to score 61 won. Points were awarded based on the number of the ball pocketed.

Eventually it dawned on the players that you could win just by making five balls even if your opponent made ten!

The next evolution of the game was Continuous Pool. Continuous Pool was the father of Straight Pool. Continuous pool was played for 50 to over 1,000 points, the scores were kept continuously from rack to rack and whoever sank the last ball broke the next rack. Continuous pool became the championship game, and reigned supreme until it was replaced by straight pool in 1910.

The big differences between Continuous and Straight (14.1 Continuous) is that after 14 balls have been pocketed, the last ball stays on the table in its position, in order to be used as a break ball for the next rack which is composed of the remaining 14 balls (no head or apex ball), and the tournament matches were usually played to 150 points.

For decades Straight Pool was the Championship Game and it produced many of the very greatest pool players including Alfredo De Oro, Ralph Greenleaf, Irving Crane, Joe Balsis, Jimmy Caras, Andrew Ponzi, Erwin Rudolph, Willie Mosconi, Arthur "Babe" Crandall, Steve Mizerak, Jim Rempe, and Mike Sigel.