Question: Which offices were held by the politicians who held their allegiance to the union of american civil war?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/allegiance> <http://dbpedia.org/resource/Union_(American_Civil_War)> . ?x <http://dbpedia.org/property/office> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/OfficeHolder>}