Check out Ken Burns' documentary entitled "Th West". The massacre of Native Americans in California in the 1840s and 50s and the use of the term will tell you that it was no badge of honor. That is revisionist history bs. Hell, all you have to do is look at the cowboy flicks in the movies and on tv when I was a kid (1950s) and context will tell that the term Redskin wasn't used very kindly.
I think luvherd was referring to the use of the term "Redskins" when originally adopted by the ownership when they were forced to change their name (from Boston Braves to Boston Redskins), not when the term was first used in describing Native Americans, which is a correct/accurate factual statement.
I think I have discussed this before, but I'll repeat a few things. When I started law school in 1998, Harjo (the original challenger to the Washington Redskins trademark) was in year six of her challenge. When I studied "Trademark Law and Unfair Competition" of the first time in Spring 2000, the case had been up and down through the administrative appeal and civil appeal process a couple of times, and at that point, the DC Circuit Court of Appeals had sent it back to the USPTO and had overturned the PTO's cancellation of the marks. Fourteen years later, and Harjo has the same re-occurring and inescapable problem (as do copy-cat challengers):
the evidence necessary to cancel a trademark based on the allegation that the mark is scandalous or disparaging of a group of people is consumer survey evidence, where the average consumer is asked several questions, including how they perceive and associate the trademark(s).
In every proper consumer survey, the overwhelming majority of the consuming public associates "Washington Redskins" and "Redskins" with an NFL franchise and not with Native Americans, which makes sense because you rarely hear someone use the term "redskin" in reference to a Native American or group of Native Americans. Until (and unless) the consuming public's perception changes so that "Washington Redskins" and "Redskins" are associated with Native Americans, there is no legal basis for cancelling the franchise's trademark.
In addition, people seem to have this misconception that if the marks are cancelled, the use of the terms and logos will vanish. It won't. Instead, what will happen, is that use may diminish over the years, but importantly, the profits from such use will be spread amongst third-parties (rather than monopolized by the NFL through their agreement with the franchises that pools/splits revenue from trademark licensing/sales).