Was Philip Vian the officer holding a sword during the Altmark boarding?
Short answerProbably not; a reservist from HMS President serving with a destroyer boarding party is a more plausible candidate, though the identification is not certain.
NotesThe sword story is an identification problem rather than a settled anecdote. Reservists from HMS President had been moved from a cruiser into destroyer boarding parties, giving the operation personnel from a unit with a strong sword-drill tradition. That background makes a cruiser reservist a plausible source for the weapon seen in accounts of the boarding. A cruiser reservist remains a reasoned candidate rather than proof that Vian personally carried the sword.