The attribution has been confirmed by Professor Ekhart Berckenhagen, in a letter dated July 1977 which is accompanies the present lot.
Cunningham followed his father, a Jacobite, into European exile aged only three. In 1745 they had fled Scotland and settled in Italy where he trained in both Rome and Naples. Having once painted the king of Denmark whilst staying in Paris, he won many subsequent commissions from European high society. Although successful, he was also extravagant, and in 1777 bankruptcy compelled him to leave England again, for St. Petersburg. He joined the Duchess of Kingston's train, and then entered the service of Catherine the Great. Cunningham subsequently travelled to Berlin, but after his return to London he squandered his money and died destitute in 1795.