Silver and gold watch

Why might this watch have found its way into a museum collection?

This oval shaped watch with a gold dial is said to have belonged to Oliver Cromwell. Cromwell (1599-1658) played an important part in the Civil War and the downfall of Charles I. He signed Charles I’s death warrant in 1649 and was made Lord Protector of England from 1653 to 1658. Gallery 2: The Ashmolean Story

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