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.
Francis I, Duke of Saxe-Lauenburg Francis I of Saxe-Lauenburg (1510 – 19 March 1581, Buxtehude) was the eldest child and only son of Duke Magnus I of Saxe-Lauenburg and Catherine of Brunswick-Wolfenbüttel (1488 – 29 July 1563, Neuhaus), daughter of Duke Henry IV "the Evil" of Brunswick and Lunenburg (Wolfenbüttel). Francis I succeeded his father in 1543 as duke of Saxe-Lauenburg, but resigned in favour of his major son Magnus II in 1571. Two years later he reascended and was succeeded by Francis II in 1581.