According to Tony Collins (RL Historian and RFL Archivist)
Quote Of all the clubs currently playing rugby league, Bradford were the first to be founded in 1863 (actually one interesting point is that they were formed well before the RFU was founded in 1871).
I know some people argue that they went bust in 1964 or that the majority of the original club went over to soccer in 1907 and became Bradford Park Avenue, but there was/is a living continuity in terms of club administrators, players and supporters. Huddersfield were founded the following year and Hull FC in 1865.
It’s important that we celebrate the history of our clubs - when the 2013 World Cup takes place it will mark 150 years of rugby league history. These clubs are older than the vast majority of clubs playing any football code around the world. It’s a great opportunity for the game as a whole. '"
Our first game at Thrum Hall was against Hull FC in 1886. The current clubs that were part of the forming of the Northern Union were formed as follows. Searched the web for the info and is as follows
BRADFORD (1863) Was formed as Bradford Football club but only played Rugby
LEEDS (1873) Started out as Leeds St.Johns but probably formed from a merger of sports clubs
ROCHDALE (1871) On the 20th of April 1871, the directors of Rochdale Wasps, Rochdale United and Rochdale Football Club met at the Roebuck Hotel in the town centre to form a senior team that would represent the town.
WIGAN (1872)
WAKEFIELD (1873)
HALIFAX (1873)
ST.HELENS (19th November 1873)
WIDNES (1875)
OLDHAM (1876) though it missed a season when the Bears went bust.
HUDDERSFIELD (187icon_cool.gif Was a cricket club in 1864, that added football and rugby at a later date (187icon_cool.gif
LEIGH (187icon_cool.gif
WARRINGTON (1879) Unclear when exactly as a team was playing from 1873, but officially 1879 as Warrington Zingari.
BATLEY (1880)
HUNSLET (1883) Again another team that has question marks about its existence since 1883!
and adopted Italians . 
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