what is the {start time} for {Portuguese Empire} has {capital} as {Lisbon} ?
What year did Lisbon become the capitol of Portuguese?
When did Lisbon become the capital of the Portuguese Empire?
SELECT ?f WHERE { resource:Portuguese_Empire property:capital ?q . ?q property:capital resource:Lisbon . ?q property:start_time ?f }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q200464> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P36> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q597> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q200464 p:P36 ?s . ?s ps:P36 wd:Q597 . ?s pq:P580 ?value}