Fare-thee-well Royal Scots.

[matteus the inbred]

I think the Coldstream Guards are the oldest regiment in the British Army with a continual existence, founded in 1650. However, the original formations that now make up the Royal Scots were raised in 1633 for foreign service in France, and seem to have been fully regularised when they got back in 1661. 'Pontius Pilate's Bodyguard' are therefore considered the most 'senior' unit in the Army.