Claims about the oldest serving military units depend on how continuity is defined. The Honourable Artillery Company is dated to 1537, the Scots Guards to 1642, the Coldstream Guards to 1650, the Grenadier Guards to 1656, and the Royal Marines to 1664. The Yeomen of the Guard are treated separately as a ceremonial body rather than a serving regiment. The American 181st Infantry Regiment provides another kind of claim through its descent from Massachusetts Bay Colony militia. Comparing those examples requires distinguishing current service, ceremonial status, and inherited organizational lineage.
Notable Point · 3:49:12-3:51:27
How old military-unit lineages are compared
Claims about the oldest serving formations depend on whether continuity is traced through a present regiment, a ceremonial body, or inherited militia lineage.