 On Angus'return in 1542, he was still in contact with Henry VIII, and allowed Sir Ralph Sadler, English ambassador to Scotland, to reside at Tantallon during the attempts to negotiate a marriage between the infant Mary, Queen of Scots, and Edward, Prince of Wales in 1542 – 43. It has been claimed that when the Earl of Hertford invaded Scotland in 1544, during the ensuing War of the Rough Wooing, Tantallon was bypassed by the English army, due to the Earl's English sympathies, though the castle of Oliver Sinclair is listed amongst places burnt by the returning English army in contemporary sources, but it was left unmolested in 1547. Angus was finally imprisoned at Blackness Castle in 1544, after which he changed sides to support the Scottish cause. The gunners of Tantallon were rewarded in August 1548, after firing on English ships during an engagement in the Firth of Forth.
