Hi Nick as has been pointed out the Green flag is the flag of Hepburn's who previously fought under Gustavus Adolphus as the Famed "Green Brigade". He then entered the service of the French as was he suposeduly sick of the put downs he received for being a Roman Catholic supposudly being one of the reasons. This Regiment did go on to form the Royal Scots. I have the colours for Hepburn's Regiment on the webiste in the TYW French Range.
The Plain Saltire is a good safe shout but a Green one is also plausable imo maybe out of respect for Hepburn. It might also explain the picture in the Lace Wars Rule book.
Some more info for you below.
The Royal Scots (The Royal Regiment)
1625.03.28 John Hepburn's Regiment
1627 entered Danish service
1630 entered Swedish service, formed with Mackay's Highlanders (raised 1626), Stargate's Corps, and Lumsden's Musketeers, the Green or Scots Brigade
1633 remnants of Green Brigade merged into Hepburn's Regt
1633.01.26 Royal Regiment of Foot
placed on Scottish establishment for King Charles I's Scottish coronation
1635 Régiment de Hebron [Hepburn]
entered French service
1637 Régiment de Douglas
1655.10.21 Régiment de Dumbarton
1662 transferred to English service; ranked as 1st regiment of foot
1662 returned to French service
1667 returned to English service for Dutch war
1667 returned to French service
1678 returned to English Establishment
1684.05.01 His Majesty's Royal Regiment of Foot
also known until 1751 by the names of colonels
1747 ranked as 1st Foot
1751.07.01 1st (Royal) Regiment of Foot
1812.02.11 1st Regiment of Foot (Royal Scots)
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