Flag of the Commonwealth of England.
An Ordinance of 12 April 1654 ordered: "That the arms of Scotland viz: a Cross commonly called the St Andrew's Cross be received onto and borne from henceforth in the Arms of this Commonwealth ... etc".

According to W. G. Perrin, British Flags (Cambridge, 1922, p. 64), the saltire of Scotland did not reappear on naval flags until an Order of the Council of State dated 18 May 1658 (the jack) and from c. 1653 (the flag of subordinate Generals at Sea continuing as the impaled arms of England and Ireland). Christopher Southworth, 16 May 2010, Flags of the World
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