The Contract With God Trilogy by Will Eisner is considered to be the first graphic novel. It's actually three parts as the name implies: A Contract With God, A Life Force, and Dropsie Avenue. It takes place in New York during the 1930s.
I've spent a fair amount time in New York City because my family is from there and my grandpa grew up during the Great Depression probably in a similar setting. There's also a lot of Yiddish colloquialisms that I'd never picked up before. Since I come from a Jewish family, I'm assuming some expressions have just fallen into disuse. It's amazing that even 80 years ago, the city was so developed; at least, coming from someone who lives in suburbia, it shows that even almost a century doesn't make a difference, it's still nothing like living in the city.
I enjoyed reading it to an extent, but it wasn't my favorite. I found some of it humorous, and the art interesting, and the writing consistent. Dropsie Avenue was kind of drawn out and has no chapters to separate it. The avenue is really the main character, as opposed to people, but that also made it interesting too. The other two stories are interesting as well, although memorable mainly for their art and the struggles the characters endure. For the first graphic novel it is still entirely readable.