Striking colours

Definition

Lowering a vessel’s ensign as the conventional signal of surrender. A vessel that struck her colours was understood to have ceased resistance and was no longer to be fired upon; her crew became prisoners of the captor under the customary maritime law of the period. The same gesture in reverse — raising a previously-concealed flag as a vessel closed to combat range — was the standard form by which a pirate or privateer announced his identity to a target.