Endor?
I don't know; having trouble thinking of one. I'm sure there's an incredibly obvious one I'm overlooking. Wikipedia says the battle of the Ebro did not go well for the Republicans.
Edit: More from Wikipedia: Eurymedon (Wars of the Delian League), Evesham (Second Barons' War). I don't know, the list of E-battles doesn't seem that compelling. I'm trying to think of some smaller engagements from the First or Second World Wars that might fit.

Edit: More from Wikipedia: Eurymedon (Wars of the Delian League), Evesham (Second Barons' War). I don't know, the list of E-battles doesn't seem that compelling. I'm trying to think of some smaller engagements from the First or Second World Wars that might fit.