Rule 42, which prohibits the use of GAA property for games with interests in conflict with the interests of the GAA – such games are referred to by some as "garrison games" or "foreign sports". In practice, the rule has only been applied to the sports of soccer, and rugby, which were perceived to be rivals to the playing of Gaelic games. Not all such codes were successful – Swedish football was created from a mixture of rugby and soccer rules, but was overtaken by soccer. International appeal By the end of the 19th century, rugby football and rugby union had spread far and wide. This spread was by no means confined to the British Empire. Rugby football was an early arrival in Germany. The first German rugby team existed at Neuenheim College – now called Heidelberg College – in Heidelberg. Around 1850, the game started to attract the attention of the students. Students under the guidance of the teacher Edward Hill Ullrich were the ones who then founded the rugby department of the Heidelberger Ruderklub von 1872/Heidelberger Flaggenklub was established. (HRK 1872) in 1891, which today claims to be the oldest German rugby club. The oldest still existing rugby department within a club is that of DSV 78 Hannover, formed in 1878 by Ferdinand-Wilhelm Fricke. German rugby has traditionally been centred on Heidelberg and Hanover, but has spread over the entire country in recent decades. In the United States, rugby football-like games were being played early. For example, Princeton University students played a game called "ballown" in 1820. All of these games remained largely "mob" style games, with huge numbers of players attempting to advance the ball into a goal area, often by any means necessary. By the 1840s, Harvard, Yale and Princeton were all playing rugby football stemming partly from Americans who had been educated in English schools. However, in 1862, Yale dealt it a major blow by banning it for being too violent and dangerous. Unfortunately, American football's growth came at exactly the point at which rugby was beginning to establish itself in the States: in 1869, the first game of American football was played between Princeton and Rutgers, with rules substantially identical to rugby. However, by 1882, the rules' innovations of Walter Camp, like the snap and downs, had distinguished the American game from rugby. Rugby union also reached South America early, a continent with few