John Hamilton-Leslie fought on the side of a King of Great Britain and Ireland who was the ruler of the Duchy and Electorate of Brunswick-Luneburg in what empire?
George I of Great Britain: George I (George Louis; German: "Georg Ludwig" ; 28 May 1660 – 11 June 1727) was King of Great Britain and Ireland from 1 August 1714 until his death, and ruler of the Duchy and Electorate of Brunswick-Lüneburg (Hanover) in the Holy Roman Empire from 1698.
i don't know