“What though the field be lost? all is not lost.” (Milton: Paradise Lost, i, line 105-6.) “All is lost but honour” (Tout est perdu, madame, fors l'honneur) is what François I. is said to have written to his mother, after the Battle of Pavia in 1525.
There is a somewhat strange connection between de-feat and de-feature. Defeat is the French de-fait, un-made or un-done, Latin, de-factus (defectus, our “defect”); and feature is the Norman faiture, Latin factura, the make-up, frame, or form. Hence old writers have used the word “defeat” to mean disfigure or spoil the form.
“Defeat thy favour [face] with an usurped beard.” —Shakespeare: Othello, i. 3.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894