EDIT.....haha, just realized I highlighted those 3 essential bluesmen without properly reading above where Owen says those three are your "go to" guys too......says it all really. Arguably three of the most important musical figures in history when one considers the global impact of rock n roll.
To be fair, rock and roll didn't have much to do with Chicago blues - it had much more to do with the jump blues of the 1940s. Muddy Waters was quite right when he said that the blues had a baby and they called it rock and roll, but if you want the aural illustration of that, don't listen to Muddy Waters, listen to Wynonie Harris or Big Joe Turner or Louis Jordan.
The Chicago bluesmen were awesome, but in their heyday of the 1950s they were not widely known and not widely influential, even within Chicago. It was the British blues fans who first really picked up on them and began imitating them.
In other words, Chicago blues didn't give birth to rock and roll - it gave birth to rock, which is something quite different.
Anyway, I'd echo the mention of Canned Heat as the obvious go-to 60s blues-rock band. Fleetwood Mac, in their earlier incarnation (i.e. Peter Green era), have to be included. Also, although they're rather later, I would recommend the Fabulous Thunderbirds. You might also like Johnny Winter, though he's perhaps an acquired taste, and of course Stevie Ray Vaughan.
In addition to the other "proper" blues musicians mentioned, I'd say that anyone interested in this sort of thing should listen to John Lee Hooker, Albert King, and also the later work of Freddie King (the earlier work is great, but less rocky). If you want to try 80s-style blues-rock then I suppose the first person to go for is Robert Cray, normally classified as blues but really closer to rock, at least during that period.
For more British-type blues, John Mayall is the one to look for. I would also recommend Cyril Davies, if you can find anything by him - one of the very first British blues musicians. I have heard only a single track by him but it was brilliant.
Oh, and it's funny that no-one's mentioned him, but surely the greatest blues-rocker of all time - Hendrix?