Nail Your Colours to the Mast

Rooted in a real Age of Sail naval practice. A warship's flag, its "colours," legally had to be flying for the ship to keep fighting; lowering it was the recognised signal of surrender. Nailing the flag to the mast made it physically difficult to lower, a visible declaration that the crew intended to fight to the end rather than surrender under fire. The earliest known figurative use of the phrase in print is in Sir Walter Scott's 1808 poem Marmion, in a passage praising the politician Charles James Fox's defiant stand against Napoleonic France: "And nail'd her colours to the mast!"