The history of rugby union follows from various football games long before the 19th century, but it was not until the middle of that century that the rules were formulated and codified. The code of football later known as rugby union can be traced to three events: the first set of written rules in 1845, the Blackheath Club's decision to leave the Football Association in 1863 and the formation of the Rugby Football Union in 1871. The code was originally known simply as "rugby football". It was not until a schism in 1895, over the payment of players, which resulted in the formation of the separate code of rugby league, that the name "rugby union" was used to differentiate the original rugby code. For most of its history, rugby was a strictly amateur football code, and the sport's administrators frequently imposed bans and restrictions on players who they viewed as professional. It was not until 1995 that rugby union was declared an "open" game, and thus professionalism was sanctioned by the code's governing body, World Rugby—then known as the International Rugby Football Board (IRFB).