One of the under-rated greats, Joseph Keppler was an Austrian immigrant to the US, and a founder of the satirical magazine "Puck".
When you look at his images, they divide rather neatly into issues which seem so contemporary that you could run them today (immigration, corruption of Congress by monied interests), and then other issues that are just historical curiosities.
On immigration, for example, consider this one
The title is a little hard to read, its
"Looking Backward: They would close to the newcomer the bridge that carried them and their fathers over"
I really like the visual conceit here, that the shadow cast reflects the histories of the men-- its a trick that Francis Ford Coppola used in Dracula, I'd be curious to see other instances
All of Keppler's work is now public domain, and there are a few internet archives, you can start here:http://xroads.virginia.edu/~ma96/puck/toons.html
(much of this material relates to now-obscure controversy as to whether Ulysses S Grant might seek a third term)