Samuel Gompers is one of those names you vaguely remember from AP U.S. History, along with The Grange and the Know-Nothings. They fit in somehow, but you don’t exactly remember why. While he may not be on the tips of people’s tongues, he does have a rather large monument on Massachusetts Avenue NW near Mount Vernon Square. Gompers, born in London in 1850, was a major figure in the American labor movement, organizing and…