Question: When did John Stuart, 3rd Earl of Bute begin serving as Secretary of State for the Northern Department?
Paraphrase: John Stuart, 3rd Earl of Bute served as Secretary of State for the Northern Department beginning when?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q294651 p:P39 ?s . ?s ps:P39 wd:Q3954358 . ?s pq:P580 ?value}