CLEAN PASTURES is a play on words, as the year before this film debuted, a film with an all-Black cast, GREEN PASTURES, was released in theaters to White and Black audiences alike.
This is one of the so-called "Censored 11"--Looney Toons cartoons that were pulled from the market in the 1960s because of racist stereotypes of Blacks. While the general feeling of the reviewers is that this isn't offensive or that offensive, I can see how calling Heaven "Pair O Dice" could easily offend, as showing Black men as shiftless gamblers was a common stereotype of the age. As for the people who are parodied (mostly Black jazz musicians), I don't think this was intended as offensive and I bet most of them (such as Cab Calloway and Louis Armstrong) were probably flattered by the attention. Throwing in a Steppin Fetchit-inspired character, though, is inflammatory as he is practically the poster child for the "I hate my race and will whore myself out for money" club. The bottom line is that there are elements of this film that can't help but offend. This is sad, as because with a few minor changes, this could be a more acceptable and widely enjoyed cartoon.
My advice is that this and all the Censored 11 cartoons should not be shown on broadcast television unless they are shown with some sort of prologue that could explain the context and reasons they offend. Having them continue to be available on the internet (when you can find them) isn't a bad thing, however, as I am loathe to ban any sort of speech and it is an unfortunate but important part of our history. And if we eliminate EVERYTHING that might offend from our history, then we are left with,...well,...nothing!