It ran on HBO from like 2002-2008. It didn't fare well during it's run for a number of reasons. Basically though, a cast of 80% black people didn't market well, unfortunately. The Shield's success also took a lot of the limelight.
I don't use this resource to say X show is better than Y show, but as a simple common vote of the best TV series ever, The Wire is #1 (well, #1 of shows with plots haha):
IMDb: Highest Rated TV Series With At Least 5,000 Votes
Being completely honest here, the show is so good and real that there are classes on the show at Harvard, Yale, Oxford, etc. Screw taking Intro to Pop Culture 101.....every university should have a semester of just watching The Wire if you really want to know what life is like for the "have-nots." It shows the urban life angle (and I'm not giving anything away, just proclaiming the intricacy) from the drug dealers and the law enforcement, and then the dealers/cops and drug trafficking, and then dealers/cops/trafficking and politics, and then dealers/cops/tracking/politics and inner-city public schools/youth, and then in the fifth season it's all of that and journalism. Really the only area I think they missed is medicine and ER abuse...but then again the show is f*cking perfect and doesn't lack at all. It's exponentially more amazing.
Soooo you watch The Wire, and I'll watch Game of Thrones. Awesome. Meet back here in a month. Go!