Question: Which country had the county seats as History of Trier and Mediolanum?
SPARQL query: SELECT DISTINCT ?uri WHERE { ?uri <http://dbpedia.org/ontology/capital> <http://dbpedia.org/resource/History_of_Trier> . ?uri <http://dbpedia.org/ontology/capital> <http://dbpedia.org/resource/Mediolanum> . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Country>}
Answer: [Roman Empire] is the country whose capitals are History of Trier and Mediolanum.