Period      Description   SEVENTH CENTURY  ca. 630      First federation of Bulgar tribes formed. 681      Byzantine Empire recognizes first Bulgarian state.  NINTH CENTURY  811      First Bulgarian Empire defeats Byzantine Empire, begins      expanding. 870      Tsar Boris I accepts Christianity (Eastern Rite Orthodox) for      Bulgaria. 893-927      Reign of Tsar Simeon, first golden age  maximum size of First      Bulgarian Empire.  TENTH CENTURY  924      Simeon defeated by Byzantines  first empire begins decline.  ELEVENTH CENTURY  1014      Byzantines inflict major military loss on Tsar Samuil. 1018      Bulgaria becomes part of Byzantine Empire.  TWELFTH CENTURY  1185      Asen and Peter lead revolt against Byzantine Empire,      reestablishing Bulgarian state with capital at Turnovo.  THIRTEENTH CENTURY  1202      Tsar Kaloian makes peace with Byzantine Empire, achieves full      independence, and begins Second Bulgarian Empire. 1204      Treaty with Rome recognizes pope and consolidates western      border of Bulgarian Empire. 1218-1241      Reign of Ivan Asen II, second golden age of Bulgaria and      period of territorial expansion 1241      Tatar raids and feudal factionalism begin, causing social and      political disorder. 1277      Peasant revolt  "swineherd tsar" Ivailo takes power. ca. 1300      Tatar raids end.  FOURTEENTH CENTURY  1323-1370      Under Mikhail Shishman and Ivan Aleksandur, territorial and      commercial expansion resumes. 1385      Sofia captured by Ottoman Empire. 1389      Turks defeat Serbs at Kosovo Polje, exposing remaining      Bulgarian territory to Ottoman occupation.  FIFTEENTH CENTURY  1453      Constantinople falls to Ottoman Empire, ending Byzantine      Empire.  SIXTEENTH CENTURY  ca. 1600      Ottoman Empire reaches peak of its power and territorial      control.  SEVENTEENTH CENTURY  1688      Suppression of Bulgarian revolt against Ottomans at Chiprovets      ends Catholic influence in Bulgaria.  EIGHTEENTH CENTURY  1741      Hristofor Zhefarovich completes his Stematografia,      seminal work on Bulgarian cultural history. 1762      Paisi of Hilendar writes a history of the Bulgarian people,      using vernacular Bulgarian.  NINETEENTH CENTURY  1804      Serbia is the first Slavic land to take arms against Ottoman      Empire. 1806      Sofronii Vrachanski publishes first book printed in Bulgaria. 1815      Bulgarian volunteers join Serbian independence fighters. ca. 1820      End of kurdzhaliistvo, anarchic period      precipitated by breakdown of Ottoman authority in Bulgarian      territory. 1835      Neofit Rilski opens first school teaching in Bulgarian, using      Petur Beron's secular education system. 1840      First girls' school teaching in Bulgarian opens. 1844      First periodical printed in Bulgaria. 1856      First chitalishte (public re 1000
 eading room) opens. 1860      Bishop Ilarion Makariopolski declares Bulgarian diocese of      Constantinople independent of Greek Orthodox patriarchate. 1862      Georgi Rakovski forms first armed group for Bulgarian      independence. 1870      Bulgarian Orthodox Church declared a separate exarchate by      Ottoman Empire. 1875      September Uprising, first general Bulgarian revolt against      Ottoman rule, crushed. 1876      April Uprising spurs massacres of Bulgarians by Ottomans and      European conference on autonomy for Christian subjects of      Ottoman Empire. 1878       Russo-Turkish War of 1877-78 ends in Treaty of San Stefano,      creating an autonomous Bulgaria stretching from Aegean Sea to      Danube. 1878      In Treaty of Berlin, Western Europe forces revision of Treaty      of Berlin, returning area south of Balkan Mountains to Ottoman      Empire  a smaller Bulgaria retains autonomy within the empire. 1879      Turnovo constitution written as foundation of Bulgarian state       Alexander of Battenburg elected prince of Bulgarian      constitutional monarchy. 1886      Alexander deposed by army officers. 1887      Stefan Stambolov begins seven years as prime minister,      accelerating economic development  Ferdinand of Saxe-Coburg-      Gotha accepts Bulgarian throne. 1891      Social Democratic Party, later Bulgarian Communist Party,      founded. 1899      Bulgarian Agrarian Union founded to represent peasant      interests.  TWENTIETH CENTURY  1903      Suppression of Ilinden-Preobrazhensko Uprising sends large      numbers of Macedonian refugees into Bulgaria and inflames      Macedonian issue. 1908      Ferdinand declares Bulgaria fully independent of Ottoman      Empire and himself tsar. 1912      First Balkan War pushes Ottoman Empire completely out of      Europe  Bulgaria regains Thrace. 1913      In Second Balkan War, Bulgaria loses territory to Serbia and      Greece  Bulgarian nationalism on the rise. 1915-18      Bulgaria fights in World War I on side of Central Powers       decisive defeat at Dobro Pole (1918) forces Ferdinand to      abdicate in favor of his son Boris III. 1919      Treaty of Neuilly-sur-Seine awards Thrace to Greece,      Macedonian territory to Yugoslavia, Southern Dobruja to      Romainia, sets Bulgarian reparations, and limits Bulgarian      army. 1919      Under Prime Minister Aleksandur Stamboliiski, agrarians become      dominant political party  socialist parties also profit from      postwar social unrest. 1923      After four years of drastic economic reform and suppression of      opposition, Stamboliiski assassinated by Macedonian      extremists. 1923-1931      Coalition Tsankov and Liapchev governments suppress      extremists  social tensions rise with world economic crisis of      1929. 1934      In Balkan Entente, Greece, Romania, Turkey, and Yugoslavia      reaffirm existing Balkan borders  Bulgaria refuses      participation, is isolated. 1934      Right-wing coup by Zveno coalition begins dictatorship,      abolishes political parties  Macedonian terrorism ends. 1935      Boris III deposes Zveno and declares royal dictatorship that      remains in effect until 1943. 1941      Bulgaria signs Tripartite Pact, allying it with Nazi Germany      in World War II  Bulgaria refrains from action against Soviet      Union for duration of war. 1943      Boris III dies, leaving three-man regency to rule for his      underage son Simeon II. 1943-44      Allied air raids damage Sofia heavily  activity of antiwar      factions in Bulgaria increases. 1944      As Bulgarian government seeks peace with Allies, Red Army      invades  temporary Bulgarian government overthrown by      communist-led coalition. 1946      Georgi Dimitrov of the Bulgarian Communist Party (BCP) becomes      prime minister of the new Republic of Bulgarian. 1947      Dimitrov constitution goes into effect  remaining opposition      parties to BCP silenced  state confiscation of private      industry completed. 1948-49         Muslim, Orthodox, Protestant, and Roman Catholic r
 ed6eligiousus      organizations restrained or banned. 1949      Joseph V. Stalin chooses Vulko Chervenkov to succeed Dimitrov       period of Stalinist cult of personality, purges of Bulgarian      BCP, and strict cultural and political orthodoxy begins. 1950      Large-scale collectivization of agriculture begins, continuing      through 1958. 1953      Death of Stalin begins loosening of Chervenkov's control,      easing of party discipline. 1956      Todor Zhivkov becomes first secretary of BCP. 1957-58      After Soviet invasion of Hungary, Bulgaria cracks down on      nonconformism to party line in culture and politics. 1962      Nikita S. Khrushchev annoints Todor Zhivkov as successor to      Chervenkov  Zhivkov becomes prime minister and is unchallenged      leader for the next twenty-seven years. 1968      Soviet invasion of Czechoslovakia tightens government control      in Bulgaria. 1971      New constitution specifies role of BCP in Bulgarian society      and politics. 1978      Dissident Georgi Markov assassinated in London. 1981      Economic restructuring in New Economic Model brings temporary      economic upswing, no long-term improvement. 1981      Under direction of Liudmila Zhivkova, Bulgaria celebrates its      1,300th anniversary. 1984      First program of assimilation of ethnic Turkish minority      begins. 1987-88      Dissident groups begin to form around environmental and human      rights issues. 1989      Summer Second Turkish assimilation program brings massive      Turkish emigration, increased dissident activity, and      international criticism. 1989      Fall Massive antigovernment demonstrations trigger party      dismissal of Zhivkov. 1990 Three BCP-dominated governments are      formed and dissolved  round table discussions between BCP and      opposition parties begin to formulate reform legislation. 1990      June First multiparty national election since World War II      gives majority in National Assembly to Bulgarian Socialist      Party (BSP  formerly BCP) with large opposition block to Union      of Democratic Forces (UDF), which has refused participation in      government. 1990      July Tent-city demonstrations begin in Sofia, continue through      summer. 1990      August UDF leader Zheliu Zhelev chosen president. 1990      September Zhelev meets with French and American leaders,      receives pledges of economic support. 1990      November-December General strike forces resignation of      government of Prime Minister Andrei Lukanov  interim coalition      government formed under Dimitur Popov. 1991      January Initial phase of economic reform, including price      decontrol on some commodities, goes into effect. 1991      Spring Arable Land Law begins redistribution of land to      private farmers. 1991      July New constitution approved by National Assembly  national      elections set for October. 

Data as of June 1992