user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: What eastern European country was ruled by Igor of Kiev? 
Knowledge Triplets: Eastern Europe, location.location.partiallycontains, m.0wg9204
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Mstislav I of Kiev
m.0gl21lt, military.military_combatant_group.conflict, Ukrainian War of Independence
Eastern Europe, common.topic.webpage, m.09ysrxm
Russo-Turkish War, time.event.locations, Eastern Europe
Kiev Offensive, base.culturalevent.event.entity_involved, Józef Piłsudski
Ukrainian Soviet Socialist Republic, location.location.containedby, Soviet Union
Eastern Europe, location.location.partiallycontains, m.0wg91_p
Moldova, location.location.containedby, Eastern Europe
Carnegie Moscow Center, common.topic.subjects, Eastern Europe
Kievan Rus', location.location.geolocation, m.07mpqcf
Eastern Europe, location.location.contains, Caucasus
Eastern Europe, location.location.partiallycontains, m.0wg91_v
Second Battle of Kharkov, time.event.locations, Ukrainian Soviet Socialist Republic
Igor of Kiev, common.topic.notable_for, g.125ghc5yw
Kievan Rus', base.schemastaging.context_name.pronunciation, g.125_qn892
Vsevolod I of Kiev, common.topic.notable_types, Monarch
Igor of Kiev, royalty.kingdom.rulers, Kievan Rus'
Eastern Europe, location.location.contains, Southern Carpathians
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Igor of Kiev
Eastern Europe, location.location.containedby, Kievan Rus'
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Yaropolk I of Kiev
Kievan Rus', royalty.kingdom.rulers, Vladimir the Great
Sviatoslav I of Kiev, people.person.place_of_birth, Kiev
Ukraine, location.country.form_of_government, Republic
m.0wg91_p, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Eastern Europe, common.topic.webpage, m.09wst1h
Ukraine, common.topic.notable_types, Country
Ukrainian Soviet Socialist Republic, common.topic.notable_types, Country
Eastern Europe, location.location.contains, Romania
Central Europe, location.location.events, Ukrainian War of Independence
Kievan Rus', royalty.kingdom.rulers, Yaroslav the Wise
Crimea, location.location.containedby, Eastern Europe
Eastern Europe, book.book_subject.works, A Hole in the Heart of the World: Being Jewish in Eastern Europe
Vsevolod I of Kiev, people.person.parents, Yaroslav the Wise
Second Polish Republic, location.location.containedby, Eastern Europe
Sviatoslav II of Kiev, people.person.gender, Male
m.09xyt2j, common.webpage.topic, Eastern Europe
Kievan Rus', common.topic.notable_for, g.1256bs13g
Revolution In Eastern Europe, freebase.valuenotation.has_value, Start date
Revolution In Eastern Europe, freebase.valuenotation.has_no_value, Instance of recurring event
Kiev, location.location.events, Battle of Bystryk
Kurmangazy District, location.location.containedby, Eastern Europe
Iziaslav I of Kiev, royalty.monarch.royal_line, Rurik dynasty
Eastern European anti-Communist insurgencies, common.topic.notable_types, Military Conflict
Eastern Europe, location.location.contains, Georgia
Eastern Europe, location.location.partially_contains, Terekti District
Eastern Europe, location.location.contains, Taskala District
Ship burial of Igor the Old in 945, depicted by Heinrich Semiradski (1845-1902)., common.image.appears_in_topic_gallery, Norse funeral
Sviatoslav I of Kiev, common.topic.image, Madrid Skylitzes. Meeting between John Tzimiskes and Sviatoslav.
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Sviatopolk II of Kiev
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Forest Brothers
Ukraine, location.location.events, Mongol invasion of Rus'
m.02bk_9p, common.image.appears_in_topic_gallery, Eastern Europe
Eastern Europe, common.topic.webpage, m.09x1bwr
Olga of Kiev, people.person.nationality, Russia
Olga of Kiev, royalty.monarch.royal_line, Rurik dynasty
Yaroslav the Wise, people.person.children, Iziaslav I of Kiev
Western Europe, common.topic.image, m.02bk_9p
Kaztal District, location.location.containedby, Eastern Europe
Ukraine, location.location.events, Polish–Soviet War
Ship burial of Igor the Old in 945, depicted by Heinrich Semiradski (1845-1902)., common.image.appears_in_topic_gallery, Igor of Kiev
Vitaly Primakov, military.military_person.participated_in_conflicts, Ukrainian–Soviet War
Central Europe, location.location.events, Eastern Front
Kievan Rus', location.location.containedby, Rus'
Eastern Europe, location.location.contains, Zhanybek District
Kievan Rus', royalty.kingdom.rulers, Igor of Kiev
Polish–Soviet War, military.military_conflict.military_personnel_involved, Józef Kowalski
Kiev, location.location.containedby, Ukrainian Soviet Socialist Republic
m.09x1bwr, common.webpage.topic, Eastern Europe
Rus', common.topic.image, Kievan Rus en
Country, common.topic.notable_types, Kievan Rus'
Rus', location.location.containedby, Eastern Europe
Socialist Federal Republic of Yugoslavia, location.location.containedby, Central and Eastern Europe
Igor of Kiev, people.deceased_person.place_of_death, Korosten
Battle of Arcadiopolis, base.culturalevent.event.entity_involved, Kievan Rus'
West Kazakhstan Region, location.location.partially_containedby, Eastern Europe
Location-Europe-UNsubregions, Kosovo as part of Serbia, common.image.appears_in_topic_gallery, Eastern Europe
Olga of Kiev, people.person.parents, Oleg of Novgorod
Sviatoslav II of Kiev, people.person.place_of_birth, Kiev
Sviatoslav I of Kiev, common.topic.article, m.0b3t7
Eastern Europe, location.location.contains, Socialist Federal Republic of Yugoslavia
Central and Eastern Europe, location.location.contains, Socialist Federal Republic of Yugoslavia
Kievan Rus', location.location.containedby, Eastern Europe
Sviatoslav I of Kiev, royalty.monarch.royal_line, Rurik dynasty
Ukraine, location.location.primarily_containedby, Eastern Europe
Oral, location.location.containedby, Eastern Europe
Revolution In Eastern Europe, time.event.locations, Eastern Europe
m.03z9745, military.military_combatant_group.combatants, Ukrainian People's Republic
Ukrainian Soviet Socialist Republic, military.military_combatant.military_conflicts, m.0gl21lt
Ukrainian–Soviet War, base.culturalevent.event.entity_involved, Russian Soviet Federative Socialist Republic
Soviet Union, location.location.contains, Ukrainian Soviet Socialist Republic
Eastern Europe, location.location.contains, Bulgaria
m.04z3lbb, military.military_combatant_group.conflict, Ukrainian War of Independence
Eastern Europe, organization.organization_scope.organizations_with_this_scope, Exclaimer
Ukrainian War of Independence, base.culturalevent.event.entity_involved, West Ukrainian People's Republic
Kiev Offensive, military.military_conflict.combatants, m.04yx29p
Ukraine, location.location.events, Kiev Offensive
Ukrainian–Soviet War, base.culturalevent.event.entity_involved, Ukrainian Soviet Socialist Republic
Igor of Kiev, people.person.spouse_s, m.0j4k65s
Soviet westward offensive of 1918–19, time.event.included_in_event, Ukrainian War of Independence
Iziaslav I of Kiev, people.person.parents, Yaroslav the Wise
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Vsevolod II of Kiev
Kievan Rus', common.topic.image, Location of Rus'
Akzhaik District, location.location.partially_containedby, Eastern Europe
Eastern Europe, location.location.contains, Kievan Rus'
Collision and Collusion: The Strange Case of Western Aid to Eastern Europe, 1989-1998, book.written_work.subjects, Eastern Europe
Sviatoslav I of Kiev, people.person.parents, Igor of Kiev
Romania, location.location.containedby, Eastern Europe
Sviatoslav I of Kiev, people.person.nationality, Ukraine
Kiev Offensive, time.event.included_in_event, Polish–Soviet War
Iziaslav I of Kiev, people.person.children, Yaropolk Izyaslavich
Vladimir the Great, royalty.monarch.kingdom, Kievan Rus'
Rus', location.location.contains, Kievan Rus'
m.04z3lb5, military.military_combatant_group.conflict, Ukrainian War of Independence
Sviatoslav I of Kiev, people.deceased_person.place_of_death, Khortytsia
Eastern Europe, location.location.contains_major_portion_of, Zelenov District
Eastern European anti-Communist insurgencies, time.event.locations, Soviet Union
Sviatoslav I of Kiev, people.person.children, Oleg of the Drevlyans
Kiev Offensive, base.culturalevent.event.entity_involved, Ukrainian People's Republic
m.04yx348, military.military_combatant_group.conflict, Polish–Ukrainian War
Eupraxia of Kiev, common.topic.notable_types, Monarch
Kiev Offensive, base.culturalevent.event.entity_involved, Ukrainian Soviet Socialist Republic
Hungarian invasions of Europe, time.event.locations, Eastern Europe
m.0j4k65s, people.marriage.spouse, Igor of Kiev
Sviatoslav II of Kiev, common.topic.notable_types, Monarch
Eastern Europe, location.location.events, Revolution In Eastern Europe
Sviatoslav I of Kiev, people.person.religion, Paganism
Ukrainian Soviet Socialist Republic, location.country.capital, Kiev
Eastern Europe, location.location.events, Great Patriotic War
Eastern Europe, common.topic.webpage, m.09xf_cx
Olga of Kiev, people.person.religion, Paganism
Eupraxia of Kiev, royalty.monarch.royal_line, Rurik dynasty
Eastern Europe, location.location.contains, Bokey Orda District
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Cursed soldiers
m.09y0w8l, common.webpage.topic, Eastern Europe
Zelenov District, location.location.primarily_containedby, Eastern Europe
Peremyotnoye, location.location.containedby, Eastern Europe
Austro-Turkish War, time.event.locations, Eastern Europe
Sviatoslav I of Kiev, people.person.children, Vladimir the Great
Europe (UN divisions Eastern, East Central and Southeastern Europe), common.image.appears_in_topic_gallery, Eastern Europe
Kievan Rus', common.topic.image, Kievan Rus en
Atyrau, location.location.partially_containedby, Eastern Europe
m.0ngz9h3, people.marriage.spouse, Sviatoslav I of Kiev
Igor of Kiev, royalty.monarch.kingdom, Kievan Rus'
Hungarian invasions of Europe, base.culturalevent.event.entity_involved, East Francia
Eastern Europe, common.topic.webpage, m.09x6gcq
Ukraine, location.country.capital, Kiev
Ukrainian War of Independence, common.topic.image, Eastern Front of World War I in 1917
m.0wg8sxb, location.partial_containment_relationship.partially_contained_by, Ukraine
Eastern Europe, location.location.partially_contains, Inder District
m.04yx29p, military.military_combatant_group.conflict, Kiev Offensive
Kievan Rus', common.topic.image, Varangian routes
Ukrainian People's Republic, common.topic.notable_types, Location
Exclaimer, organization.organization.geographic_scope, Eastern Europe
Igor of Kiev, common.topic.article, m.014x2s
Olga of Kiev, people.person.children, Sviatoslav I of Kiev
Bulgaria, location.location.containedby, Eastern Europe
Igor of Kiev, common.topic.image, Radzivill Igor-945
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Sviatoslav II of Kiev
Vladimir the Great, people.person.parents, Sviatoslav I of Kiev
m.0105ybrn, award.award_honor.honored_for, Revolution In Eastern Europe
Ukrainian Soviet Socialist Republic, location.location.contains, Kiev
Iziaslav I of Kiev, people.person.children, Sviatopolk II of Kiev
Eastern Europe, location.location.people_born_here, Sam Borenstein
Pavlo Shandruk, military.military_person.participated_in_conflicts, Ukrainian–Soviet War
Ukrainian Soviet Socialist Republic, location.location.events, Second Battle of Kharkov
Eastern Europe, common.topic.webpage, m.0b464l5
Eastern Europe, common.topic.webpage, m.09y405k
Socialist Federal Republic of Yugoslavia, location.location.containedby, Eastern Europe
Ukrainian War of Independence, time.event.locations, Central Europe
m.09xplj_, common.webpage.topic, Eastern Europe
Soviet Union, location.location.events, Eastern European anti-Communist insurgencies
Eastern Europe, location.location.partiallycontains, m.0wg91_j
Ukrainian War of Independence, base.culturalevent.event.entity_involved, Second Polish Republic
Eastern Europe, location.location.events, Austro-Turkish War
Eastern Europe, location.location.contains, Second Polish Republic
Kiev, location.location.events, Battle of Wołodarka
Ukrainian War of Independence, base.culturalevent.event.entity_involved, Ukrainian Soviet Socialist Republic
Polish–Soviet War, base.culturalevent.event.entity_involved, Ukrainian Soviet Socialist Republic
Vsevolod I of Kiev, people.person.gender, Male
Eastern Europe, location.location.events, Hungarian invasions of Europe
Soviet westward offensive of 1918–19, base.culturalevent.event.entity_involved, Ukrainian People's Republic
Eastern Europe, location.location.events, Great Northern War
Europe, base.locations.continents.countries_within, Ukraine
Igor of Kiev, royalty.monarch.royal_line, Rurik dynasty
Olga of Kiev, people.person.spouse_s, m.0j4k65s
Eastern European anti-Communist insurgencies, common.topic.article, m.0gls5gc
Eupraxia of Kiev, people.family_member.family, Rurik dynasty
Kiev Offensive, common.topic.notable_types, Military Conflict
Eastern Front, time.event.locations, Central Europe
Vsevolod I of Kiev, people.family_member.family, Rurik dynasty
m.0j4k65s, people.marriage.spouse, Olga of Kiev
Russian Empire, location.location.contains, Kiev
Ukrainian War of Independence, common.topic.article, m.03cr0dw
Kievan Rus', common.topic.article, m.0c824
Eastern Europe, location.location.contains, Kingdom of Romania
Igor of Kiev, people.person.parents, g.1q5gn997m
Vsevolod I of Kiev, people.person.children, Eupraxia of Kiev
Ukrainian–Soviet War, base.culturalevent.event.entity_involved, Ukrainian People's Republic
Eastern Europe, location.location.contains, Grand Duchy of Lithuania
Kiev, location.location.containedby, Russian Empire
Sviatoslav II of Kiev, royalty.monarch.royal_line, Rurik dynasty
Eastern Europe, location.location.contains, Galicia
Eastern Europe, common.topic.webpage, m.09x5w5d
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Iziaslav I of Kiev
Sviatoslav I of Kiev, people.person.gender, Male
Ukrainian Soviet Socialist Republic, location.location.events, Dnieper–Carpathian Offensive
Eastern Europe, location.location.contains, Kurmangazy District
Eastern Europe, common.topic.image, Location-Europe-UNsubregions, Kosovo as part of Serbia
Igor of Kiev, people.person.religion, Paganism
Collision and Collusion: The Strange Case of Western Aid to Eastern Europe, 1989-1998, common.topic.article, m.075xffj
Igor of Kiev, people.person.parents, Rurik
Ukrainian War of Independence, base.culturalevent.event.entity_involved, French Third Republic
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Sviatopolk I of Kiev
Eastern Europe, location.location.contains, Rus'
Igor of Kiev, people.person.gender, Male
Kiev, base.biblioness.bibs_location.country, Ukraine
Polish–Ukrainian War, base.culturalevent.event.entity_involved, West Ukrainian People's Republic
m.09x_z_s, common.webpage.topic, Eastern Europe
Georgia, location.location.containedby, Eastern Europe
Eastern Europe, common.topic.subject_of, Carnegie Moscow Center
Ukrainian Soviet Socialist Republic, location.location.events, Barvinkove-Losowaja Operation
Iziaslav I of Kiev, people.person.gender, Male
m.09wgvm6, common.webpage.topic, Eastern Europe
Eastern Europe, location.location.partially_contains, Atyrau Region
Eastern Europe, location.location.events, Polish–Soviet War
Eastern Europe, base.schemastaging.context_name.pronunciation, g.125_llnl3
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Vsevolod I of Kiev
Revolution In Eastern Europe, common.topic.notable_for, g.1q56fr7j6
Igor of Kiev, common.topic.notable_types, Monarch
Sviatoslav II of Kiev, people.deceased_person.place_of_death, Kiev
Kievan Rus', royalty.kingdom.rulers, Sviatoslav I of Kiev
Eastern Europe, base.ontologies.ontology_instance.equivalent_instances, m.09klpb1
m.0111bzrq, location.partial_containment_relationship.partially_contained_by, Ukraine
Eastern Europe, common.topic.notable_for, g.1258n9r3m
Kiev, location.location.containedby, Ukraine
Central and Eastern Europe, common.topic.notable_types, Region
Yaroslav the Wise, people.person.place_of_birth, Kiev
Ukrainian War of Independence, common.topic.notable_for, g.1255bdmf_
Eastern Europe, location.location.partiallycontains, m.0wg91_c
Terekti District, location.location.partially_containedby, Eastern Europe
Eastern Europe, common.topic.webpage, m.09wgvm6
Eastern Europe, location.location.events, Eastern European anti-Communist insurgencies
Eastern Europe, location.location.contains, Belarusian Central Council
Sviatoslav I of Kiev, royalty.monarch.kingdom, Kievan Rus'
Yaroslav the Wise, people.person.nationality, Kievan Rus'
Kievan Rus', royalty.kingdom.rulers, Olga of Kiev
Eastern Europe, common.topic.article, m.09b6m
Eastern Europe, location.location.contains, Zhanakala District
Central Europe, location.location.partially_contains, Ukraine
Polish–Soviet War, base.culturalevent.event.entity_involved, Ukrainian People's Republic
Europe (UN divisions Eastern, East Central and Southeastern Europe), common.image.size, m.02dv17n
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Viacheslav I of Kiev
Eastern Europe, common.topic.image, Europe (UN divisions Eastern, East Central and Southeastern Europe)
Eastern Europe, location.location.contains, Crimea
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Romanian anti-communist resistance movement
Parliamentary republic, government.form_of_government.countries, Ukrainian People's Republic
Ukrainian War of Independence, base.culturalevent.event.entity_involved, Ukrainian People's Republic
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Sviatoslav I of Kiev
Ukrainian Soviet Socialist Republic, military.military_combatant.military_conflicts, m.03z96cw
Eastern Europe, location.location.events, Austro-Russian–Turkish War
Eastern Europe, location.location.partially_contains, Akzhaik District
Eastern Europe, location.location.contains, Moldova
Ukrainian War of Independence, time.event.locations, Eastern Europe
Eastern Europe, location.location.events, Russo-Turkish War
Revolution In Eastern Europe, award.award_winning_work.awards_won, m.0105ybrn
m.09klpb1, base.ontologies.ontology_instance_mapping.freebase_topic, Eastern Europe
m.09xgv8w, common.webpage.topic, Eastern Europe
Revolution In Eastern Europe, freebase.valuenotation.has_value, People involved
Eastern Europe, location.location.containedby, Europe
Caucasus, location.location.containedby, Eastern Europe
Ukraine, location.location.partially_containedby, Central Europe
Belarusian People's Republic, location.location.containedby, Eastern Europe
Vsevolod I of Kiev, people.person.place_of_birth, Russia
Ukrainian People's Republic, military.military_combatant.military_conflicts, m.04z3lb5
Rus', location.location.contains, Kiev
Sam Borenstein, people.person.place_of_birth, Eastern Europe
Eastern Europe, location.location.contains, Kaztal District
Kiev Offensive, base.culturalevent.event.entity_involved, Edward Rydz-Śmigły
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Yaropolk II of Kiev
Igor of Kiev, common.topic.image, Ship burial of Igor the Old in 945, depicted by Heinrich Semiradski (1845-1902).
North Caucasus, location.location.containedby, Eastern Europe
Eastern Europe, location.location.partially_contains, Atyrau
Polish–Ukrainian War, base.culturalevent.event.entity_involved, Ukrainian People's Republic
m.09x5w5d, common.webpage.topic, Eastern Europe
Eastern Europe, location.location.events, Polish–Swedish War
Eupraxia of Kiev, people.person.parents, Vsevolod I of Kiev
Vladimir the Great, people.person.nationality, Kievan Rus'
Sviatoslav I of Kiev, common.topic.notable_for, g.125fqjjjq
m.0wg91_c, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Ukraine, location.location.containedby, Eurasia
m.03z96cw, military.military_combatant_group.combatants, Ukrainian Soviet Socialist Republic
Kiev Offensive, base.culturalevent.event.entity_involved, Second Polish Republic
Ukrainian People's Republic, location.country.form_of_government, Parliamentary republic
Sviatoslav II of Kiev, people.person.parents, Yaroslav the Wise
Kiev Offensive, base.culturalevent.event.entity_involved, Mikhail Tukhachevsky
Eastern Europe, common.topic.webpage, m.09xgv8w
Eastern Europe, location.location.events, Tokhtamysh–Timur war
Old East Slavic, language.human_language.main_country, Kievan Rus'
m.0wg91_j, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Ship burial of Igor the Old in 945, depicted by Heinrich Semiradski (1845-1902)., common.image.appears_in_topic_gallery, Ship burial
Yaroslav the Wise, people.person.children, Vsevolod I of Kiev
Galicia, location.location.containedby, Eastern Europe
Kiev, location.location.containedby, Rus'
Kievan Rus', location.country.capital, Kiev
Radzivill Igor-945, common.image.size, m.02b99nw
m.04z4k94, people.place_lived.location, Eastern Europe
Ship burial of Igor the Old in 945, depicted by Heinrich Semiradski (1845-1902)., common.image.size, m.029ln1x
m.04z3lb5, military.military_combatant_group.combatants, Ukrainian People's Republic
Southern Carpathians, location.location.containedby, Eastern Europe
Isatay District, location.location.containedby, Eastern Europe
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Hungarian Revolution of 1956
Eastern Europe, location.location.events, Ukrainian War of Independence
Eupraxia of Kiev, people.person.gender, Female
Ukraine, base.aareas.schema.administrative_area.administrative_children, Kiev
Eastern Europe, location.location.contains, Isatay District
m.0gl21lt, military.military_combatant_group.combatants, Ukrainian Soviet Socialist Republic
Kiev, base.aareas.schema.administrative_area.administrative_parent, Ukraine
Ukrainian People's Republic, location.country.capital, Kiev
Eastern European anti-Communist insurgencies, common.topic.notable_for, g.1255l1vcg
Korostens’kyi Raion, location.administrative_division.country, Ukraine
Kievan Rus', royalty.kingdom.rulers, Oleg of Novgorod
m.09x6gcq, common.webpage.topic, Eastern Europe
Kiev, location.administrative_division.country, Ukraine
Prut, location.location.containedby, Eastern Europe
Kievan Rus', location.country.official_language, Old East Slavic
Polish–Soviet War, time.event.locations, Eastern Europe
Vladimir the Great, people.person.children, Sviatopolk I of Kiev
Eastern Front, time.event.locations, Eastern Europe
Revolution In Eastern Europe, freebase.valuenotation.is_reviewed, Location(s)
Ukraine, location.location.events, Ukrainian–Soviet War
Kiev, freebase.valuenotation.is_reviewed, Time zone(s)
Eastern European anti-Communist insurgencies, time.event.locations, Eastern Europe
m.09y405k, common.webpage.topic, Eastern Europe
m.0wg9209, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Kiev Offensive, base.culturalevent.event.entity_involved, Semyon Budyonny
Atyrau Region, location.location.partially_containedby, Eastern Europe
Ukrainian War of Independence, base.culturalevent.event.entity_involved, Kingdom of Romania
Kiev Offensive, base.culturalevent.event.entity_involved, Russian Soviet Federative Socialist Republic
Kiev, location.location.events, Battle of Boryspil
Belarusian Central Council, location.location.containedby, Eastern Europe
Sviatoslav I of Kiev, common.topic.image, Lebedev Svyatoslavs meeting with Emperor John
m.09wst1h, common.webpage.topic, Eastern Europe
Eastern Europe, location.location.contains_major_portion_of, Ukraine
Eastern Europe, location.location.contains, Belarusian People's Republic
Inder District, location.location.partially_containedby, Eastern Europe
Vsevolod I of Kiev, people.person.children, Vladimir II Monomakh
Sviatoslav I of Kiev, common.topic.notable_types, Monarch
Revolution In Eastern Europe, common.topic.notable_types, Award-Winning Work
Eastern Europe, location.location.events, Eastern Front
m.09xf_cx, common.webpage.topic, Eastern Europe
Igor of Kiev, common.topic.article, m.0374jr
Sviatoslav II of Kiev, people.family_member.family, Rurik dynasty
Eastern Europe, location.location.contains, Prut
Eastern Europe, common.topic.webpage, m.09x_z_s
Kresy, location.location.containedby, Eastern Europe
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Eastern Bloc
Iziaslav I of Kiev, people.family_member.family, Rurik dynasty
Austro-Russian–Turkish War, time.event.locations, Eastern Europe
Kiev Offensive, time.event.locations, Ukraine
Polish–Soviet War, time.event.includes_event, Kiev Offensive
Eastern Europe, location.location.partiallycontains, m.0wg91__
Yaroslav the Wise, people.person.children, Sviatoslav II of Kiev
Sviatoslav I of Kiev, people.person.spouse_s, m.0ngz9h3
m.0wg91__, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Radzivill Igor-945, common.image.appears_in_topic_gallery, Igor of Kiev
Sviatoslav I of Kiev, people.person.children, Yaropolk I of Kiev
Kievan Rus', location.location.events, Bolesław I's intervention in the Kievan succession crisis
Kiev, common.topic.notable_types, City/Town/Village
Eastern Europe, common.topic.webpage, m.09xyt2j
Eastern Europe, common.topic.webpage, m.09y0w8l
Kievan Rus', common.topic.notable_types, Country
Eastern Europe, location.location.people_born_here, Vena Kava
Eastern Europe, location.location.contains, Kresy
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Eupraxia of Kiev
Kazakhstan, location.location.partially_containedby, Eastern Europe
Olga of Kiev, common.topic.notable_types, Monarch
Ukraine, location.location.containedby, Europe
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Olga of Kiev
Olga of Kiev, people.deceased_person.place_of_death, Kiev
Sviatoslav I of Kiev, people.person.parents, Olga of Kiev
m.0b464l5, common.webpage.topic, Eastern Europe
Ukrainian People's Republic, military.military_combatant.military_conflicts, m.03z9745
Rurik, people.person.children, Igor of Kiev
Eastern Europe, location.location.contains, North Caucasus
Ukraine, location.location.events, Soviet westward offensive of 1918–19
Eastern Europe, location.location.contains, Oral
Eastern Europe, location.location.partiallycontains, m.0wg91_6
Kingdom of Romania, location.location.containedby, Eastern Europe
Eastern Europe, common.topic.webpage, m.09xplj_
m.0wg9204, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Ukraine, base.locations.countries.continent, Europe
Eastern Europe, location.location.partially_contains, Makhambet District
Revolution In Eastern Europe, time.event.included_in_event, Revolutions of 1989
Eastern Europe, book.book_subject.works, Collision and Collusion: The Strange Case of Western Aid to Eastern Europe, 1989-1998
Revolution In Eastern Europe, freebase.valuenotation.has_value, End date
Central and Eastern Europe, location.location.containedby, Europe
Yaroslav the Wise, royalty.monarch.kingdom, Kievan Rus'
Soviet westward offensive of 1918–19, time.event.included_in_event, Ukrainian–Soviet War
Iziaslav I of Kiev, common.topic.notable_types, Monarch
m.0wg91_v, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Eastern Europe, common.topic.notable_types, Location
Olga of Kiev, people.person.gender, Female
Eastern Europe, location.location.partiallycontains, m.0wg9209
Eastern Europe, location.location.contains, Peremyotnoye
Eastern European anti-Communist insurgencies, base.culturalevent.event.entity_involved, Ukrainian Insurgent Army
Olga of Kiev, royalty.monarch.kingdom, Kievan Rus'
Eastern Europe, common.topic.image, m.02bk_9p
Eastern Europe, location.location.partially_contains, Kazakhstan
Eupraxia of Kiev, people.deceased_person.place_of_death, Kiev
Dnieper–Carpathian Offensive, time.event.locations, Ukrainian Soviet Socialist Republic
Vena Kava, people.person.place_of_birth, Eastern Europe
m.0wg91_6, location.partial_containment_relationship.partially_contained_by, Eastern Europe
Eastern Europe, location.location.partially_contains, West Kazakhstan Region
Vsevolod I of Kiev, royalty.monarch.royal_line, Rurik dynasty
Rurik dynasty, royalty.royal_line.monarchs_from_this_line, Oleg of Novgorod
Grand Duchy of Lithuania, location.location.containedby, Eastern Europe
m.09ysrxm, common.webpage.topic, Eastern Europe
Igor of Kiev, people.person.children, Sviatoslav I of Kiev

Answer: Kievan Rus'