Bulgars in the context of "Tengrism"

Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey to the south, Serbia and North Macedonia to the west, and Romania to the north. It covers a territory of 110,994 square kilometres (42,855 sq mi) and is the tenth largest within the European Union and the sixteenth-largest country in Europe by area. Sofia is the nation's capital and largest city; other major cities include Burgas, Plovdiv, and Varna.

One of the earliest societies in the lands of modern-day Bulgaria was the Karanovo culture (6,500 BC). In the 6th to 3rd century BC, the region was a battleground for ancient Thracians, Persians, Celts, and Macedonians; stability came when the Roman Empire conquered the region in AD 45. After the Roman state splintered, tribal invasions in the region resumed. Around the 6th century, these territories were settled by the early Slavs. The Bulgars, led by Asparuh, attacked from the lands of Old Great Bulgaria and permanently invaded the Balkans in the late 7th century. They established the First Bulgarian Empire, victoriously recognised by treaty in 681 AD by the Byzantine Empire. It dominated most of the Balkans and significantly influenced Slavic cultures by developing the Cyrillic script. Under the rule of the Krum's dynasty, the country rose to the status of a mighty empire and great power. The First Bulgarian Empire lasted until the early 11th century, when Byzantine emperor Basil II conquered and dismantled it. A successful Bulgarian revolt in 1185 established a Second Bulgarian Empire, which reached its apex under Ivan Asen II (1218–1241). After numerous exhausting wars and feudal strife, the empire disintegrated and in 1396 fell under Ottoman rule for nearly five centuries.

The Byzantine–Bulgarian wars were a series of conflicts fought between the Byzantine Empire and the Bulgarian Empire which began after the Bulgars conquered parts of the Balkan peninsula after 680 AD. The Byzantine and First Bulgarian Empire continued to clash over the next century with varying success, until the Bulgarians, led by Krum, inflicted a series of crushing defeats on the Byzantines. After Krum died in 814, his son Omurtag negotiated a thirty-year peace treaty. Simeon I had multiple successful campaigns against the Byzantines during his rule from 893 to 927. His son Peter I negotiated another long-lasting peace treaty. His rule was followed by a period of decline of the Bulgarian state.

In 971 John I Tzimiskes, the Byzantine emperor, subjugated much of the weakening Bulgarian Empire by defeating Boris II and capturing Preslav, the Bulgarian capital. Samuel managed to stabilize the Bulgarian state with its center around the town of Prespa. Near the end of his rule, the Byzantines regained the upper hand, and under Basil II they won the Battle of Kleidion and completely conquered Bulgaria in 1018. There were rebellions against Byzantine rule from 1040 to 1041, and in the 1070s and the 1080s, but these failed. In 1185, however, Theodore Peter and Ivan Asen started a revolt, and the weakening Byzantine Empire, facing internal dynastic troubles of its own, was unable to quash the revolt.

The First Bulgarian Empire (Church Slavonic: блъгарьско цѣсарьствиѥ, romanized: blŭgarĭsko tsěsarǐstvije; Bulgarian: Първо българско царство) was a medieval state that existed in Southeastern Europe between the 7th and 11th centuries AD. It was founded in 680–681 after part of the Bulgars, led by Asparuh, moved south to the northeastern Balkans. There they secured Byzantine recognition of their right to settle south of the Danube by defeating – possibly with the help of local South Slavic tribes – the Byzantine army led by Constantine IV. During the 9th and 10th century, Bulgaria at the height of its power spread from the Danube Bend to the Black Sea and from the Dnieper River to the Adriatic Sea and became an important power in the region competing with the Byzantine Empire.

As the state solidified its position in the Balkans, it entered into a centuries-long interaction, sometimes friendly and sometimes hostile, with the Byzantine Empire. Bulgaria emerged as Byzantium's chief antagonist to its north, resulting in several wars. The two powers also enjoyed periods of peace and alliance, most notably during the Second Arab Siege of Constantinople, where the Bulgarian army broke the siege and destroyed the Arab army, thus preventing an Arab invasion of Southeastern Europe. Byzantium had a strong cultural influence on Bulgaria, which also led to the eventual adoption of Christianity in 864. After the disintegration of the Avar Khaganate, the country expanded its territory northwest to the Pannonian Plain. Later the Bulgarians confronted the advance of the Pechenegs and Cumans, and achieved a decisive victory over the Magyars, forcing them to establish themselves permanently in Pannonia.

Asparuh (also Ispor or (rarely) Isperih) was а Bulgar khan in the second half of the 7th century and is credited with the establishment of the First Bulgarian Empire in 681.

Old Great Bulgaria (Medieval Greek: Παλαιά Μεγάλη Βουλγαρία, Palaiá Megálē Voulgaría), also often known by the Latin names Magna Bulgaria and Patria Onoguria ("Onogur land"), was a 7th-century Turkic nomadic empire formed by the Onogur-Bulgars on the western Pontic–Caspian steppe (modern southern Ukraine and southwest Russia). Great Bulgaria was originally centered between the Dniester and lower Volga.

The original capital was Phanagoria on the Taman Peninsula between the Black and Azov seas. In the mid-7th century, Great Bulgaria expanded west to include Avar territory and was centered on Poltava. During the late 7th century, however, an Avar-Slavic alliance in the west, and Khazars in the east, defeated the Bulgars, and Great Bulgaria disintegrated. Successor states are the First Bulgarian Empire and Volga Bulgaria.

The Migration Period (c. 300 to 600 AD), also known as the Barbarian Invasions, was a period in European history marked by large-scale migrations that saw the fall of the Western Roman Empire and subsequent settlement of its former territories by various tribes, and the establishment of post-Roman kingdoms there.

The term refers to the important role played by the migration, invasion, and settlement of various tribes, notably the Burgundians, Vandals, Goths, Alemanni, Alans, Huns, early Slavs, Pannonian Avars, Bulgars and Magyars within or into the territories of Europe as a whole and of the Western Roman Empire in particular. Historiography traditionally takes the period as beginning in AD 375 (possibly as early as 300) and ending in 568. Various factors contributed to this phenomenon of migration and invasion, and their role and significance are still widely discussed.

The walls of Constantinople (Turkish: Konstantinopolis Surları; Greek: Τείχη της Κωνσταντινούπολης) are a series of defensive stone walls that have surrounded and protected the city of Constantinople (modern Fatih district of Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built.

Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger. They saved the city, and the Byzantine Empire with it, during sieges by the Avar–Sassanian coalition, Arabs, Rus', and Bulgars, among others. The fortifications retained their usefulness even after the advent of gunpowder siege cannons, which played a part in the city's fall to Ottoman forces in 1453 but were not able to breach its walls.

The Battle of Ongal took place in the summer of 680 in the Ongal area, an unspecified location in and around the Danube Delta near the Peuce Island, present-day Tulcea County, Romania. It was fought between the Bulgars of Asparuh of Bulgaria, who had recently invaded the Balkans, and the Byzantine Empire, which ultimately lost the battle. The battle was crucial for the creation of the First Bulgarian Empire.