The coat of arms of the district Heilbronn

The coat of arms of the district Heilbronn shows a clipped silver eagle in a red field.
He stems from the earl von Lauffen's coat of arms. This eagle probably goes back to the royal eagle and can be seen as allusiona to the royal court that the earls von Lauffen governed.
The clipping could then be seen as rang difference showing coat of arms 
diminution.