what is the {point in time} for {American Samoa} has {ethnic group} as {Samoans} ?
When did the American Samoa's start going by Samoans?
When were American Samoa named ethnic group as Samoans?
SELECT ?l WHERE { ?n property:ethnic_group resource:Samoans . ?n property:point_in_time ?l . resource:American_Samoa property:ethnic_group ?n }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q16641> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P172> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q1135531> .
?statement <http://www.wikidata.org/entity/P585> ?value. 
} 

SELECT ?value WHERE { wd:Q16641 p:P172 ?s . ?s ps:P172 wd:Q1135531 . ?s pq:P585 ?value}