Why did it split, and why did they make the rules difference?
Oh sorry I thought you already knew about league and union. Rugby union is already the full contact collision sport for europe. It is popular in England (the Aviva Premiership), France (the extremely wealthy Top14) and Ireland, Wales, Scotland (Guinness Pro12) and Italy (not really that popular but they do have two pretty shit teams in the Pro12). It's also very popular in several 'tier 2' nations like Georgia and Romania, and many more if you include Rugby 7s (the variant of union they played at the olympics (such as Russia, Spain, Portugal etc.).
Gonna be long post here, sorry, but I could talk about rugby for days lol.
In Europe there is only one serious rugby league competition which has teams almost exclusively in Northern England (league's traditional heartland) and one in France (Catalan Dragons), that is the Super League and is what the Wolfpack are trying to get promoted to (currently two divisions below Super League). There is also one other French team in the division below Super League from Toulouse and some terrible Welsh clubs that get a few hundred fans at best. So as I say, they probably don't see much room for expansion in Europe so hope that by getting to North America they can get a good few fans just based on sheer population size etc.
In terms of the history, basically league and union split at the end of the 19th century over the issue of professionalism. The Rugby Football Union wanted the game to remain amateur (in the same way as the olympics used to be), they thought people should play for the love of the game etc. etc. The problem was that those playing for clubs in the North of England (poorer, working class, more industrial area) could not afford to just take time off work to train and play like the better off southern players. So the northern clubs defected to create the Rugby Football League and became fully professional. Hence one code is called rugby league, the other rugby union. In England league is the working mans game and union is more upper/upper-middle class and that has carried over to other places. That's the stereotype anyway and is probably true in England still to some extent. It used to be the case in parts of Ireland that union was more middle/upper class, though not anymore really and league did not even exist here until the 1990s. Australia is the only place other than Northern England where league is the dominant rugby code and it's the same there, but in Wales or New Zealand for example, union has always been working class, middle class, and upper class, everyone played and watched it really. In the 90s union ended up going professional anyway, which is kind of funny actually, but I suppose that was pretty much one hundred years after the initial split.
Initially the games were exactly the same after the split, but as it was professional rugby league soon started changing the rules that it saw as making the game messier, more complicated and less attractive to spectators. So they changed things to speed the game up and try attract more paying customers, they reduced the number of players to 13 instead of 15 to allow for more space and made it so that the defending team had to retreat ten metres after the tackle (in union teams only have to retreat so they are behind the foot of the last player in the ruck). League also got rid of lineouts (where the ball is thrown in) and rucks (possibly the biggest change).
In union the ball is still live after the tackle (the tackled player has to release the ball) and teams 'forwards' compete for it at rucks by trying to shove the other team out of the way, or for the defending team trying to steal the ball. Rucks are great, physical contests and this contest is a key part of union, but there are lots of rules about what you can and can't do so for newcomers it might be confusing initially. They can also get somewhat messy at times. But here is what a ruck looks like:
Australian player carries the ball (yellow ), is tackled to ground and his teammate rucks over the ball to get the NZ player out of the way to secure possession for another phase:
Another example of Irish players rucking English ones out of the way:
If the defenders can get there first before a ruck is formed and avoid getting shoved out of the way, then they are entitled to steal the ball with their hands and turn the ball over:
League got rid of the rucks and replaced it with a 'play the ball'. Once a tackle is completed, the tackled player gets up and rolls the ball back through this legs to a teammate. I think originally there was still some sort of contest, but in the 70s they introduced the 6 tackle rule. Basically teams have 6 attempts to try and score a try, I guess it's along the same lines as NFL downs although it is to score rather than move the ball a set distance. Apart from the tackler and one other player (called the markers), the defending team has to get back 10 metres. Here is what that looks like for comparison:
That's three tackles, so the attacking team has three more to score before turning it over.
Both codes of rugby are great in their own ways, but the different rules make them play out a bit differently despite the same essentials (ie. scoring tries, can only pass backwards etc.). League is a more one dimensional/simplistic but is generally faster than union because there is more space and a set number of tackles, so it's very entertaining from that point of view. I always compare to it a pendulum the way the game swings back and forth, end to end quickly.
Union on the other hand is more fluid and organic with play flowing from ruck to ruck through multiple phases, each team will tend to have different periods of pressure and there are more kicking options as well as the different demands of rucks, lineouts and mauls that I already mentioned. Not to say union is slow though. Back in the amateur days it was definitely a lot messier than it is now, but teams like New Zealand have always been known for playing fast paced, 'running rugby'. France too. Now that it's fully pro the standard is much higher and the game is much faster across all teams and leagues. Used to be league would have had a higher standard as it was professional obviously.
It is possible that North Americans could take to the simplicity of league more than union, and the set of 6 rule is somewhat comparable to downs in NA football as I say.
