Oklahoma City and Norman both have major streets named Robinson and Classen. They must have been named after locally important people back when the cities were being planned, but who were they?

(Would be interested to know about the origins of some of OKC/Norman's other street names too—some are pretty obvious like Western, Eastern, and Penn(sylvania), but some of the more fanciful ones like May, Morgan, Council, and Britton could have interesting stories behind them.)