You already know the Cleveland Cavaliers of course, but the city had a rich basketball past long before they came into the picture in 1970. The Cleveland Rosenblums were one of those long-gone teams from the early 20th century, but they were also one of the most successful - and innovative.
The Rosenblums - named for owner and Cleveland department store owner Max Rosenblum - were one of the original members of the American Basketball League (a league Rosenblum helped create), playing from 1925 to 1930.
Though their run as a team was brief, the Rosenblums - also known as the Rosenblum Celtics - were incredibly successful, winning three championships. Perhaps more importantly, the Rosenblums left a lasting impact on the game of basketball itself, which was still in its infancy at this time. The Rosenblums are credited with helping to grow the game in the Midwest and developing actual plays on a possession that would open someone up for a shot, as opposed to the "mad rush up and down the floor with much running and wild shooting" as was the custom at the time. Essentially, the game of basketball was pure anarchy, and the Cleveland Rosenblums played a part in bringing some semblance of order.
Though the Rosenblums have been largely lost in basketball's now-illustrious history, they played a major part in modernizing the game and helping it survive at a time when that was no guarantee.