Doncaster had never previously won a league title despite earning promotion on two occasions.
They finished second and claimed the final promotion place in the Second Division during the 1993-94 season. They were promoted alongside league winners Workington Town, but were relegated into the second division after finishing bottom of the Rugby League Championship the following year.
In 2008 the Dons beat Oldham in the National League Two play off final. Doncaster, coached at the helm by Ellery Hanley, followed Gateshead into National League One after coming from fourth place in the play offs to achieve promotion.
RFL’s chief executive Nigel Wood congratulated the club.
He said: ““Doncaster should be justifiably proud of winning a first league title in their 61-year history and I am sure they will celebrate their success long and hard before turning their attentions to preparing for life as a Championship club.”
Wood also congratulated Wigan and Featherstone for winning their respective League Leaders Shields in the Super League and Championship divisions. It is the fourth time Wigan have finished top of Super League after the regular season, while Featherstone have won their third consecutive League Leaders Shield.
Wood said: “Wigan’s consistency in 2012 is a great credit to coach Shaun Wane, his staff and all the Wigan Warriors players and it is clear they are going to be a force to be reckoned with between now and the Super League Grand Final.
“Featherstone have been models of consistency in the last few seasons and after their defeat by Halifax in the Northern Rail Cup final earlier this year, I am sure that the Daryl Powell and his players will not relinquish their Championship title lightly.”