Bloody good work, Mr. Hector James Peabody !
What Gobbles said.
Full Steam Ahead !
Biography (edited from: http://mr-peabody-sherman.wikia.com/wiki/Mr._Peabody)
Mr. Peabody built the WABAC (before google earth) machine, as a birthday gift for Sherman (Senators).
Mr. Peabody and Sherman then go back in time to see a Roman (Carmody) speaking in Latin (Applebyism).
Mr. Peabody then adds a translator circuit to the machine, so that everyone seems to speak English, and so they go to see the Roman again, this time finding out, that he is, in actuality, only a used chariot salesman.
Their next trip is to see Ben Franklin flying his kite, but Mr Peabody and Sherman find out that they cannot interact with the past, so Mr. Peabody makes some more adjustments, thus turning the WABAC from a "time machine", into a "should have been machine".
This results in the past they visit, being totally cockeyed, and now they must save the timeline, and rewrite history.