As a state established by khan Asparoukh, Bulgaria has been existing for more than 13 centuries.
Thracians were the first settlers in the Bulgarian lands and their civilisation is evidenced by the numerous archaeological finds, uncovered tombs, discovered gold and silver treasures. Testimonies for the presence of life in the pre-historic ages have been preserved in the best-preserved Neolithic housings discovered world-wide – namely those off the town of Stara Zagora, in the “Bacho Kiro” cave off the town of Dryanovo and in the Magurata cave – close to the town of Belogradchik. The first written reference where the name “Bulgarians” is to be found is included in an anonymous Roman chronograph of 452 AD.

In the second half of the 7th century, the Proto-Bulgarians - an ethnic community of Turkic origin - settled on the territory of the present-day Northeastern Bulgaria. In alliance with the Slavs they formed the Bulgarian State, which was recognised by the Byzantine Empire in 681 AD. Khan Asparouh stood at the head of that state and Pliska was made its capital.

Under the rule of Khan Tervel (700-718 AD), Bulgaria expanded its territory and turned into a major political force. Under Khan Kroum (803-814 AD) Bulgaria bordered with the empire of Carl the Great to the west, and to the east the Bulgarian troops reached the walls of Constantinople, the capital of the Byzantine Empire. In 864 AD, during the rule of Prince Boris I Michail (852-889 AD), the Bulgarians adopted Christianity as their official religion. This act abolished the ethnic differences between Proto-Bulgarians and Slavs, and started building a unified Bulgarian nation.
After adopting Christianity, the influence of the Byzantine Empire grew. This is evidenced by the ossuary in the Bachkovo Monastery (1083 AD). Bulgarian church music was created.

In the second half of the 9th century the brothers Cyril (Constantine the Philosopher) and Methodius created and disseminated the Cyrillic alphabet. Their disciples Clement and Nahum came to Bulgaria, where they were warmly welcomed and found good conditions for work. They developed a rich educational and literary activity. From Bulgaria the Cyrillic script spread to other Slavic lands as well - present-day Serbia and Russia. The cities of Ochrida and Pliska, and subsequently the new capital city Veliki Preslav as well, became centres of Bulgarian culture, and of Slav culture as a whole.

The reign of Tsar Simeon I (893-927 AD) marked the "Golden Age of Bulgarian Culture", and the territory of his state reached the Black Sea and the Aegean Sea. During the reign of Simeon's successors, Bulgaria was weakened by internal struggles, the heresy of the priest Bogomil spread and influenced the teachings of the Cathars and Albigenses in Western Europe.

In 1018, after prolonged wars, Bulgaria was conquered by the Byzantine Empire. From the very first years under Byzantine rule, the Bulgarians started fighting for their freedom. In 1186, the uprising led by two boyars, the brothers Assen and Peter, overthrew the domination of the Byzantine Empire. The Second Bulgarian Kingdom was founded, and Turnovo became the new capital. After 1186, Bulgaria was initially ruled by Assen, and after that by Peter.
The earlier power of Bulgaria was restored during the reign of their youngest brother, Kaloyan (1197-1207), and during the reign of Tsar Ivan Assen II (1218 -1241) the Second Bulgarian Kingdom reached its greatest upsurge: political hegemony was established in Southeastern Europe, the territory of the country spread to the Black Sea, the Aegean Sea and the Adriatic Sea, the economy and culture developed.

Bulgaria reached a new peak, which lasted until the end of the Second Bulgarian Kingdom (1186-1396). The schools of literature and the arts in Turnovo developed the traditions in Bulgarian culture, which is evidenced by the frescoes in the Boyana Church, the churches in Turnovo, in the Zemen Monastery, the churches hewn into the rocks near Ivanovo, the miniatures in the Gospel that belonged to Tsar Ivan Alexander, kept at the British Museum in London, and Manassiy's Chronicle. In 1235, the Head of the Bulgarian Church was given the title of Patriarch.

The strife among some of the boyars resulted in the division of Bulgaria into two kingdoms: the kingdoms of Vidin and Turnovo. This weakened the country and it was conquered by the Ottoman Empire in 1396. For nearly five centuries Bulgaria was under Ottoman domination. The initial years were characterised by sporadic and unorganised attempts to win freedom. Later the appearance of the clandestine fighters, the “haydouts”, made the emergence of a well-organised national liberation movement possible.

The formation of the Bulgarian nation and the development of Bulgarian education started in the beginning of the 18th century. One impetus for this was the work of the monk Paissii of Hilendar History of Slavs and Bulgarians, written in 1762. The ideas of national freedom led to the establishing of an autonomous Bulgarian national Church, and to the flourishing of education and culture. Some of the key figures during the Bulgarian National Revival were Zachary Zograph, Nikolay Pavlovich, Stanislav Dospevski, and many others. That period marked also the beginning of the first amateur theatre performances.

The start of the organised revolutionary movement for liberation from Ottoman domination is associated with the work of Georgi Sava Rakovski (1821-1867) - writer and journalist, founder and ideologist of the national-liberal liberation movement.
The main figures in the national liberation movement were Vassil Levski (1837-1873) - strategist and ideologist of the movement and national hero; Lyuben Karavelov (1834-1879) - writer and journalist, leader and ideologist of the movement; Hristo Botev (1848-1876) - poet and journalist, revolutionary, democrat, national hero, and many other Bulgarians.

In 1876 the April Uprising broke out - the first significant and organised attempt at liberation from Ottoman domination. The uprising was brutally crushed and drowned in blood, but it drew the attention of the European countries to the Bulgarian national issues. In 1878, as a result of the Russian-Turkish War of Liberation (1877-1878), the Bulgarian State was restored, but national unity was not achieved. The former Bulgarian territories were divided into three: the Principality of Bulgaria was proclaimed - with Prince Alexander Battemberg at its head, Eastern Rumelia - with a Christian Governor appointed by the Sultan, while Thrace and Macedonia remained under the domination of the Ottoman Empire.

After 1878, the first cultural and educational institutions in the Principality began to be built. The St. St. Cyril and Methodius National Library was built in 1878, the St. Kliment Ohridski University of Sofia opened its doors in 1888, and the Ivan Vazov National Theatre - in 1904. The first film was shown in Rousse in 1897.
The late 19th and the early 20th century were characterised by remarkable achievements in all fine arts. That was the period marked by the works of the Bulgarian poets and writers Ivan Vazov, Aleko Konstantinov, Dimcho Debelyanov, Pencho Slaveykov - the only Bulgarian nominated for Nobel Prize, Peyo Yavorov and many others. The artists Anton Mitov, Ivan Angelov, Ivan Mrkvicka, Yaroslav Veshin, B. Schatz and others created some of the most remarkable works of art during that time. The late 19th century also marked the beginning of Bulgarian professional musical culture. The first Bulgarian composers were Emanouil Manolov, Dimiter Christov and Georgi Atanassov-Maestro.

The decision for the fractionation of Bulgaria, taken at the Berlin Congress (1878), was never accepted by the people. The decisions of 1878 triggered the Kresna-Razlog Uprising (1878-1879), which in 1885 led to the unification of the Principality of Bulgaria and Eastern Rumelia. The Ilinden-Preobrazhenie Uprising also broke out (1903).
Ferdinand Saxe-Coburg Gotha, Bulgarian Prince since 1887, proclaimed Bulgaria's independence from Turkey and in 1908 became Kniaz of the Bulgarian people. Bulgaria took part in the Balkan War (1912) and fought together with Serbia and Greece for the freedom of Thrace and Macedonia. Bulgaria won that war, but in the subsequent war among the allies (1913) it was defeated by Romania, Turkey and by its earlier allies, who tore from her territories with a Bulgarian population.

The intervention of Bulgaria in World War I on the side of the Central Powers ended with a national catastrophe. In 1918, Kniaz Ferdinand abdicated in favour of his son Boris III. The Neuilly Peace Treaty of 1919 imposed severe provisions on Bulgaria: it lost its outlet on the Aegean Sea, Western Thrace became a part of Greece, Southern Dobroudja was annexed to Romania, and the territories around Strumica, Bosilegrad, Zaribrod and villages around Kula were given to the Serbian-Croatian-Slovenian Kingdom. (Southern Dobroudja was restored to Bulgaria by the Bulgarian-Romanian Treaty of 1940.)

In the early 1940s, Bulgaria led a policy in the interest of Germany and the Axis powers. Later the participation of Bulgarian cavalry units on the Eastern Front was discontinued. Tsar Boris III supported the public pressure and did not allow the deportation of about 50,000 Bulgarian Jews.
In August 1943 Tsar Boris III died and the regency of the young Tsar Simeon II took over the governing of the country. On 5 September 1944, the Soviet Army entered Bulgaria and on 9 September the Fatherland Front Government, headed by Kimon Georgiev, came to power. In 1946 Bulgaria was proclaimed to be a People's Republic. The Queen-Mother, Tsar Simeon ?? and Princess Maria-Louisa left Bulgaria for Egypt via Turkey. The Bulgarian Communist Party came to power. The political parties outside the Fatherland Front were banned, the economy and the banks were nationalised, the arable land was coercively organised in cooperatives. The governing of the state went successively into the hands of Georgi Dimitrov, Vassil Kolarov, Vulko Chervenkov, Anton Yougov and Todor Zhivkov.

The date 10 November 1989 marked the beginning of the democratic changes in Bulgaria. A new Constitution was adopted (1991), the political parties were restored, the property expropriated in 1947 was resituated, privatisation and restitution of the land started. In 1990 Zhelyu Zhelev became President of Bulgaria - the first democratically elected President.
The key priorities in Bulgaria's foreign policy became the membership in the European Union and NATO. As a result of the country's considerable progress towards meeting the criteria for EU membership, Bulgaria received on 10 December 1999 the invitation to start the pre-accession negotiations.
The negotiations started in Brussels on 15 February 2000. On 1 December 2000, the Council of Ministers of Justice and Home Affairs of the European Union decided to remove Bulgaria from the negative visa list.