what is the {start time} for {Kingdom of England} has {instance of} as {state} ?
What year did England become an official country?
When did the Kingdom of England become a country?
SELECT ?u WHERE { FILTER ( CONTAINS ( ?a , 'http://dbpedia.org/ontology/State' ) ) . ?f rdf:type ?a . resource:Kingdom_of_England rdf:type ?f . ?f property:start_time ?u }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q179876> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P31> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://dbpedia.org/ontology/State> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q179876 p:P31 ?s . ?s ps:P31 ?x filter(contains(?x , 'http://dbpedia.org/ontology/State')) . ?s pq:P580 ?value}