Nearly four hundred years have passed since the English refugees to Germany in the reign of Mary first told the story of their exile (1554–9) in their own way. In all that time the accuracy of their version of it has never once been seriously questioned: they were protestants, forced solely for the sake of their religion to take refuge abroad from the persecution of a bigoted and cruel queen. So the record has stood.

As a mine of information for the life of John Knox, the period has been well exploited. But as an episode having dramatic unity in itself, and an historic significance out of all proportion to its duration in time, the Marian Exile has had no historian. Not since 1574, when William Whittingham first published at Zurich his polemical pamphlet under the suggestive title of The Troubles begun at Frankfort, has anyone cared to penetrate below the surface of the ingenious legend with which the fugitives cloaked the real purpose of their enterprise. For if the facts, after being arranged in their chronological sequence, are then impartially examined, there can be little doubt that the so-called ‘flight’ of 1554 was not a flight but a migration, and, as such, one of the most astute manœuvres that has ever carried a defeated political party to ultimate power.