Was someone actually thown under the bus? If not why and when did the expression start?

I thought Ipodladys answer very informative but id like to comment that ,here when the expression is used it means that a person has been unfairly betrayed in some way.

so I see a closer connotation to the" thrown to the wolves type of meaning " where someone literally gives someone up in order to save themselves . kind of like "If I just feed you to the wolves , I can get away. So maybe where Ipodlady lives it,s different and here we were just updating an old saying with a modern twist.

peace ><>

i don't know when it started, but it means when One is thrown under the bus when they are made the scapegoat or blamed for something that wasn't their responsibility in the first place. A coverup for your mistake

this is what someone says about this expression:

I think it originates from Ken Kesey's cross country trip from the West Coast to New York with a lot of his friends. Kesey had to go to New York for a new novel, "Sometimes a Great Notion". They traveled across the country on a bus they named "Furthur" (as in further). One of the sayings they developed along the way was that a person was either 'on the bus or off the bus', relating to a person's attitude - was the person part of the group and adding to their experience or was the person more interested in doing his own thing. (This from Tom Wolff's 'Electric Kool-Aid Acid Test' which documented the trip across country).

Ken Kesey became a cult idol, especially among rock musicians. The saying evolved to a person being so not 'on the bus' that they flat out 'got run over by the bus', mainly referring to a person who was a 'on the bus' wannabe, but didn't understand the bus - i.e. the rock musician who trashed his career by instantly becoming more interested in drugs, booze, and sex than in actually making any worthwhile music. In other words, the rock musician that just couldn't handle the scene.

With rock becoming more mainstream, even among lawyers and politicians, the saying evolved to throwing a person off the bus because circumstances meant the person's presence could only hurt the group regardless of his intentions and eventually to a more cold blooded variation - probably originated by the bitter members unfairly blamed for all of a groups shortcomings as they were tossed off the bus. They went into the group with the best intentions, but got chewed up by the scene ('run over by the bus') thanks to someone else actively making sure they were chewed up ('thrown under the bus' vs just being 'run over by the bus'). The phrase has basically replaced the older 'thrown to the wolves' phrase that politicians used to use.

The last part about the 'on the bus/off the bus', 'run over by the bus' evolving into 'thrown under the bus' is harder to document, but it's so close it almost has to be the source of the phrase 'thrown under the bus'.

I heard it was a reference to the depression era when buses were used more often. People who REALLY wanted the bus to stop would step out in front of it so it had to stop. People would occasionally be killed when the bus hit them. So the expression evolved from the idea that if I want to get ahead i need to stop the bus but I personally don't want to die so I throw my friend in front of the bus. Under the bus is just where they end up so the phrase is shortened to "under the bus".