clad in Stafford blue, phr. — Green’s Dictionary of Slang

clad in Stafford blue phr.

[SE clad, dressed + Stafford blue, a type of blue cloth; pun on SE staff]

bruised from a beating.

c.1460

Towneley Mysteries ‘Processus Noe Cum Fillis’ 9v: Bot thou were worthi be cled / In stafford blew For thou art alway adred.