Which son of Sophia of Hanover ruled part of the Holy Roman 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.
Landgrave Landgrave (Dutch: "landgraaf" , German: "Landgraf" ; Swedish: "lantgreve" , French: "landgrave" ; Latin: "comes magnus" , "comes patriae ", "comes provinciae ", "comes terrae ", "comes principalis ", "lantgravius ") was a noble title used in the Holy Roman Empire, and later on in its former territories. The German titles of "Landgraf ", "Markgraf " ("margrave"), and "Pfalzgraf " ("count palatine") are in the same class of ranks as "Herzog " ("duke") and above the rank of a "Graf " ("count").