The New York Rangers are one of the historic "Original Six" teams. They officially joined the NHL in the 1926-27 season. The Rangers have won the Stanley Cup four times. They defeated the Montreal Maroons in 1928 and the Toronto Maple Leafs in 1933 and 1940. It wasn't until 1994 that they won again, against the Vancouver Canucks.
The Islanders joined the league in 1972-73, as one of the earlier expansion franchises. Just seven years after their first season, the Islanders started their dynasty. From 1980 to 1984, the Islanders won four Stanley Cups in a row. In order, their victims were the Philadelphia Flyers, Minnesota North Stars, Vancouver Canucks and Edmonton Oilers. The Islanders almost won it for a fifth straight year but were bested by the Oilers in a rematch in 1985.
Despite not being an "Original Six" team, the Islanders are still a better historic team than the Rangers.
The Rangers won three of their four Stanley Cups when there were only five other teams in the league that could oppose them. And there were only six teams in the league for about forty years.
One could also make a case that the Rangers 1994 team was basically imported from Edmonton. In fact, seven players, including Mark Messier and Adam Graves, were part of the Oilers a few seasons prior to 1994.
So for being around over forty years less, the Islanders have an equal amount of Stanley Cup wins.
The Islanders have set a record across all sports, with 19 consecutive playoff series wins.
Let's not forget Mike Bossy's 50 in 50 season, where he scored 50 goals in 50 games.
Despite the Rangers raising guys like Brian Leetch, Mike Richter and Henrik Lundqvist, the Islanders have also had more success raising homegrown players.
The Islanders dynasty years roster was just about stacked with homegrown talent. Naming a few, there's Mike Bossy, Clark Gillies, Bobby Nystrom, Denis Potvin and Bryan Trottier.
As for a current homegrown player, future NHL prodigy John Tavares is on the rise after being drafted first overall in 2009.
Despite the Rangers being one of the most historic teams in the NHL, the Islanders have had more success in New York.