Superb English porcelain plate.
Hand painted with a crest 'On a ducal coronet or, a peacock in his pride ppr.'
This is probably the DE MONTMORENCY family, VISCOUNT FRANKFORT of  Ireland and Theydon Bower, Epping Essex. Possibly Viscount Lodge Raymond de Montmorency (2nd Viscount).
His son was recommended for a V.C in the Crimea and his son also received the award in the Sudan campaign.