In 1354, John de Mowbray was possibly granted, by Edward III, a Royal licence to crenellate (Caludon Castle)

There is insufficient evidence to be certain about this possible licence to crenellate.

licence said to be granted, not in the rolls.

Significant later source are;

• Stephens, W.B., 1969, 'The City of Coventry: The outlying parts of Coventry: Wyken and Caludon', VCH Warwick Vol8 p121-2
  Coventry City Library, Andrews's cuttings, iii

More details about licences to crenellate can be found here.

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