View source for Battle of Achelous (917)

{{Short description|Part of the Byzantine–Bulgarian wars}}
{{Use dmy dates|date=May 2020}}
{{Infobox military conflict
| image             = Simeon the Great anonymous seal.jpg
| caption           = Seal of Simeon I
| conflict          = Battle of Achelous
| partof            = the [[Byzantine–Bulgarian wars]] and [[Byzantine–Bulgarian war of 913–927]]
| date              = 20 August 917
| place             = [[Aheloy (river)|Achelous river]] near [[Pomorie|Anchialus]]
| coordinates       = {{Coord|42|38|35|N|27|38|12|E|region:BG-02_type:event|display=title,inline}}
| result            = Bulgarian victory
| combatant1        = [[First Bulgarian Empire|Bulgarian Empire]] <br> [[Hungarians]]
| combatant2        = [[Byzantine Empire]]
| commander1        = [[Simeon I of Bulgaria]]
| commander2        = [[Leo Phokas the Elder|Leo Phokas]]
| strength1         = 15,000<ref name="Александър Стоянов">{{Cite web |url=https://historyofwars.net/2017/03/27/battleofacheloi/ |title=Сайт на списание Военна история, 27.03.2017. Александър Стоянов, Ахелой – митове и легенди. |access-date=20 January 2019 |archive-date=19 October 2020 |archive-url=https://web.archive.org/web/20201019104051/https://historyofwars.net/2017/03/27/battleofacheloi/ |url-status=dead }}</ref>
| strength2         = 30,000<ref>Haldon, p. 92</ref><ref>Hupchick, p. 80</ref>
| casualties1       = Unknown
| casualties2       = Unknown (heavy)
}}
{{Byzantine-Bulgarian Wars}}

The '''Battle of Achelous''' or '''Acheloos''' ({{langx|bg|Битката при Ахелой}}, {{langx|el|Μάχη του Αχελώου}}),<ref>Haldon (1999), p. 212</ref> also known as the '''Battle of Anchialus''',<ref name=Stephenson23>Stephenson (2004), p. 23</ref> took place on 20 August 917, on the [[Aheloy (river)|Achelous river]] near the Bulgarian [[Black Sea]] coast, close to the fortress Tuthom (modern [[Pomorie]]) between [[First Bulgarian Empire|Bulgarian]] and [[Byzantine]] forces. The Bulgarians obtained a decisive victory which not only secured the previous successes of [[Simeon I of Bulgaria|Simeon I]], but made him ''de facto'' ruler of the whole [[Balkan Peninsula]], excluding the well-protected Byzantine capital [[Constantinople]] and the [[Peloponnese]]. The battle, which was one of the biggest and bloodiest battles of the European [[Middle Ages]], was one of the worst disasters ever to befall a Byzantine army, and conversely one of the greatest military successes of Bulgaria.<ref name="Haldon92">Haldon (2008), p. 92</ref> Among the most significant consequences was the official recognition of the [[Emperor|imperial title]] of the [[Bulgarian monarchs]], and the consequent affirmation of Bulgarian equality vis-à-vis Byzantium.

==Background==
[[File:AdrianopleConquest.jpg|250px|thumb|left|Bulgarian troops seizing Adrianople]]

After the Bulgarian victory in the [[Byzantine–Bulgarian war of 894–896|war of 894–896]], the Byzantines were forced to pay tribute to Tsar [[Simeon I of Bulgaria]]. In 912 when the Byzantine emperor [[Leo VI the Wise|Leo VI]] died, his brother [[Alexander (Byzantine emperor)|Alexander]] refused to pay tribute to the Bulgarians. Simeon saw an opportunity to [[Byzantine–Bulgarian war of 913–927|wage a new war]] and fulfil his ambitions to conquer Constantinople. Alexander died in the same year and the new government under the Patriarch [[Nicholas Mystikos]] made desperate attempts to avoid the war, promising that the infant Emperor [[Constantine VII]] would marry one of Simeon's daughters.<ref>Nicolaus Patriarcha. Epistolae, ep. 8, col. 61C-68C</ref> At some point, the patriarch and Simeon even met outside the walls of Constantinople, performing a coronation ceremony. Thereafter, Simeon began using the title "Tsar of the Bulgarians", and the Greek title ''[[basileus]]'' in his seals.<ref>Stephenson (2004), p. 22</ref>

After a plot in the Byzantine court in 914, however, the new regent [[Zoe Karbonopsina|Zoe]], Constantine's mother, rejected the marriage. In answer the Bulgarians raided eastern [[Thrace]]. [[Adrianople]] opened its gates to Simeon in September 914,<ref>Theophanes Continuatus. Chronographia, p. 387</ref><ref>Leo Grammaticus. Chronographia, p. 293–294</ref><ref>Pseudo-Simeon. Chronographia, p. 723</ref> and its population recognised Simeon as their ruler,<ref>Островски, Г. Историја Византије, с.255</ref> while the Byzantine army was occupied in the east.<ref>Georgius Monachus Continuatus. Chronicon, p. 805</ref> In the next year the Bulgarian armies attacked the areas of [[Dyrrhachium]] and [[Thessalonica]].<ref>Nicolaus Patriarcha. Epistolae, ep. 9, col. 76C</ref>

==Preparations for battle==
Both sides carefully prepared for a decisive end of the conflict. Empress Zoe wanted to swiftly make a peace settlement with the [[Arabs]] and to engage the whole army of the East in a war with Simeon and destroy him.<ref>Theophanes Continuatus. Chronographia, p. 388</ref><ref>Georgius Monachus Continuatus. Chronicon, p. 806</ref> The Byzantines tried to find allies<ref>Ioannes Skylitzes. Historia, 2, pp. 283–284</ref> and sent emissaries to the [[Magyars]], [[Pechenegs]] and [[Serbs]],<ref name="Constantinus Porphyrogenitus p. 156">Constantinus Porphyrogenitus. De administrando imperio, §32, p. 156</ref> but Simeon was familiar with the methods of Byzantine diplomacy and from the very beginning took successful actions to subvert a possible alliance between his enemies.<ref>Божилов, Ив. България и печенезите, 47–51</ref> Thus the Byzantines were forced to fight alone.{{Citation needed|date=August 2019}}

===Byzantine army===
[[File:Follis-Constantine VII and Zoe-sb1758.jpg|thumb|280px|left|Zoe of Byzantium and her son, emperor [[Constantine VII]]]]

By 917, after a series of successful campaigns, the Byzantine Empire had stabilized its eastern borders, and the generals [[John Bogas]] and [[Leo Phokas the Elder|Leo Phocas]] were able to gather additional troops from [[Asia Minor]]<ref>Leo Grammaticus. Chronographia, p. 244</ref> to reinforce the imperial ''[[tagma (military)|tagmata]]'' and the European thematic troops, gathering a force of some 60,000 men.<ref name="Haldon92"/> This was a very large army by contemporary standards, and its goal was the elimination of the Bulgarian threat from the north. The Byzantine commanders were convinced that their strategy would be successful.{{Citation needed|date=February 2009}} Morale was raised as the soldiers vowed by the miraculous [[True Cross|Cross]] to die for one another.{{Citation needed|date=February 2009}} The spirit of the army was further raised as the troops were paid in advance and a fleet commanded by [[Romanos I Lekapenos|Romanus Lecapenus]] set off to the north at the mouth of the [[Danube]]. The Byzantines had tried to pay some Pecheneg tribes to attack, but Romanus would not agree to transport them across the Danube, and instead, they attacked Bulgarian territory on their own.<ref>Nicolaus Patriarcha. Epistolae, ep. 9, col. 73A</ref>

===Bulgarian army===
The size of the Bulgarian army under [[Simeon I of Bulgaria]] is unknown.<ref name="Haldon92"/> Although they ruined the Byzantine negotiations, the Bulgarians were still afraid that the old allies of the Byzantines, the [[Pechenegs]] and the [[Hungary|Hungarians]], would attack them from the north, so two small armies were sent to protect the northern borders of the vast Bulgarian Empire that spread from [[Bosnia (region)|Bosnia]] in the west to the [[Dnieper River]] in the east.

''Miracula Sancti Georgii'', written in the 11th century and in this particular case of dubious veracity, is the only source which points that the Bulgarian army in the battle of Achelous was allied with [[Principality of Hungary|Hungarian]] and [[Pechenegs|Pecheneg]] troops,<ref>Kristó Gyula: Levedi törzsszövetségétől Szent István államáig; Magvető Könyvkiadó, Budapest, 1980 p. 248 From ''Miracula Sancti Georgii''. Hungarian translation: "''A nyugati népek, azaz a bolgárok, magyarok, szküthák, médek és türkök leghevesebb felkelése történt"'' English translation from the Hungarian: ''It was the most violent upraising of the Western nations: the Bulgarians, Hungarians, Scythians, Medians and Turks''</ref> which helped to win the victory against the Byzantine army.<ref name='Tóth'>{{cite web|first=Péter |last=Tóth |url=http://www.anale-istorie-oradea.ro/archive/Anale_Istorie_Oradea_2009.pdf | title= Pecheneg – Hungarian Reconciliation after the Defeat of Riade, p. 27 | access-date=2015-06-26}}</ref> Based on this, several historians accepted the involvement of Hungarian and Pechenegs troops, including [[Ivan Duichev]], [[Gyula Kristó]] and Ferenc Makk. Kristó even interpreted the Hungarians' participation as the "first, unmistakable sign of the decline of the Hungarian nomadic state is that from 917 onwards in the same year in two directions [i.e. west and east], the Hungarians went on raids, that is, the central control [...] began to disappear". However, contemporary sources – including a letter from Nicholas Mystikos – contradicts the chronicle's narration. Until the 930s, the Hungarians in fact were regarded as strong allies of the Byzantine Empire.<ref>{{cite book |last=Balogh |first=László |editor1-last=Révész |editor1-first=Éva |editor2-last=Halmágyi |editor2-first=Miklós |title=Középkortörténti tanulmányok. Az V. Medievisztikai PhD-konferencia (Szeged, 2007. június 7–8.) előadásai |publisher=[[University of Szeged]] |year=2007 |pages=7–21 |chapter=917. évi anchialosi csata és a magyarság [''The Battle of Achelous and the Hungarians in 917''] |isbn=978-963-482-851-8 |language=hu }}</ref> In addition, Bulgarian forces under [[Marmais]] were deployed near the western borders with the [[Serb]] principalities to prevent possible unrest.{{Citation needed|date=August 2019}}

==Battle==
{{Refimprove section|date=August 2020}}
[[File:Bitka aheloi 1 310.jpg|280px|left|thumb|The oath of the Byzantine soldiers on the eve of the battle]]

The Byzantine army marched northwards and set its camp in the vicinity of the strong fortress of Anchialus. Leo Phocas intended to invade [[Moesia]] and meet the Pechenegs and Lecapenus's troops in [[Dobrudzha]]. Simeon swiftly concentrated his army on the heights around the fortress.{{Citation needed|date=August 2019}}

On the morning of 20 August, the battle between the Bulgarians and the Byzantines began by the River [[Aheloy River|Achelous]] near the modern village [[Acheloi]], 8 kilometers to the north of Anchialus (modern [[Pomorie]]) on [[Bulgaria]]'s [[Black Sea]] coast.{{Citation needed|date=August 2019}} The Byzantine generals planned to outflank the Bulgarian right wing in order to detach Simeon's troops from the Balkan Passes.{{Citation needed|date=August 2019}} The Bulgarian ruler concentrated his most powerful forces in the two wings and left the centre relatively weak in order to surround the enemy when the centre would yield to the Byzantine attack. Simeon himself was in charge of large cavalry reserves hidden behind the hills which were intended to strike the decisive blow.{{Citation needed|date=August 2019}}

[[File:Bulgarians defeat the Byzantines at Anchialos.jpg|left|thumb|280px|The Bulgarian victory at Anchialus]]

The Byzantine attack was fierce and it was not long before the Bulgarians began slowly to retreat.<ref>Theophanes Continuatus. Chronographia, pp. 388–390</ref> The Byzantine cavalry charged the infantry in the centre killing many Bulgarians. The Bulgarian position became desperate as they could not manage to hold the heights to the south of the river and began a hasty retreat to the north. Elated, the Byzantines started a bitter chase and their battle formations soon began to break, especially as a rumour spread that the Byzantine commander, Leo Phocas, had been killed.<ref name="Haldon92"/> At this point, Simeon, who had detected the disarray in the Byzantine formation, ordered his army to stand, and, at the head of his heavy cavalry corps, attacked the Byzantine left wing from behind the hills.<ref>Leo Grammaticus. Chronographia, pp. 294–296</ref> With an irresistible onslaught the cavalry bore down at the confused enemy who immediately bent under their attack, panicked, and took to their heels.<ref>Ioannes Skylitzes. Historia, 2, pp. 284–288</ref>

{{rquote|right|...And even now there could be seen piles of bones at Anchialus, where the fleeing army of the Romans was disgracefully slain.|from [[Leo the Deacon]]'s ''History'', 75 years later<ref>Leo Diaconus, Historia, p. 124.</ref>}}

Some Byzantines tried to repulse the cavalry charge but they were also attacked by the infantry. Tsar Simeon personally took part in the fight, his white horse killed at the height of the battle. The Byzantines were completely routed. Leo Phocas was saved by fleeing to Mesembria (modern [[Nesebar]]) in [[Bulgaria]], but in the thick of the battle [[Constantine Lips]], John Grapson, and many other commanders (''archontes'') were cut down along with an enormous number of soldiers and officers.<ref>Ioannes Skylitzes. Historia, 2, p. 288</ref> By the end of the day the Bulgarians overwhelmed the defenders of Mesembria and captured the town. Leo Phocas barely escaped by boarding a ship.

The Byzantine historian [[Leo the Deacon]] says that 75 years after this military catastrophe the field at Anchialus was still covered with tens of thousands of Roman skeletons. The battle was among the bloodiest of [[medieval]] history and some historians<ref name=Dimitrov1>{{cite book|last= Bojidar|first= Dimitrov|title= Bulgaria Illustrated History|publisher= Boriana Publishing House|year= 2002|isbn= 9545000449}}</ref>{{page number|date=August 2020}} refer to it as "the battle of the century".{{Citation needed|date=August 2019}}

==Aftermath==
[[File:Battle of Anchialos (917).svg|thumb|right|Progress of the Battle of Acheloos.]]

The remainder of the Byzantine army fled all the way back to [[Constantinople]], followed by the Bulgarians. Several days later Phokas was defeated once more at [[battle of Katasyrtai|Katasyrtai]] where the last Byzantine troops were routed after a night fight.<ref>Theophanes Continuatus. Chronographia, p. 290</ref> The way to Constantinople was clear.<ref>Leo Grammaticus. Chronographia, p. 296</ref><ref>Georgius Monachus Continuatus. Chronicon, p. 808</ref> The Byzantines proposed a new peace treaty, and Simeon entered the imperial city and was crowned for a second time as "[[Tsar]]" (the [[Slavic languages|Slavonic]] title for ''[[Caesar (title)|Caesar]]'' i.e. Emperor) "of all Bulgarians and Romans".<ref>Nicolaus Patriarcha. Epistolae, ep. 9, col. 68A</ref> Simeon also demanded that his daughter would marry [[Constantine VII]], the son of empress [[Zoe Karvounopsina]], but Zoe refused and allied with [[Serbia]] and Hungary against him. However, in August 918, general Romanus Lecapenus engineered a coup to depose Zoe and confined her to the monastery of St Euphemia-in-Petrium, allowing him to assume the purple. The alliance with the Serbs postponed the decisive assault of Constantinople. Due to his also heavy casualties, Simeon decided to secure his rear and sent an army from his remaining forces under [[Marmais]] and [[Theodore Sigritsa]] to destroy them.<ref>Obolensky, D. The Byzantine Commonwealth, London, 1971, p. 111</ref> His generals captured the Serb prince<ref name="Constantinus Porphyrogenitus p. 156"/> but that gave the Byzantines precious time to recover due to his already diminished forces, making him have no sufficient forces to fight on both sides at the same time.{{Citation needed|date=August 2019}}

==Significance==
The Battle of Achelous was one of the most important battles in the long [[Byzantine–Bulgarian Wars]]. It secured the concession of the Imperial title to the Bulgarian rulers, and thereby firmly established Bulgaria's role as a key player in Europe. However, the dynastic marriage that Simeon desired to establish with the Byzantine imperial family was foiled. After his death in 927, however, his successor [[Peter I of Bulgaria|Peter I]] was able to secure the hand of Maria Lecapene, the granddaughter of Emperor Romanus I,<ref name=Stephenson24>Stephenson (2004), p. 24</ref> and with it an annual tribute, the renewed recognition of his imperial title and the [[autocephaly]] of the Bulgarian church. This agreement ushered an unprecedented period of 40 years of peaceful relations between the two powers, a time of stability and prosperity for Bulgaria.<ref>Stephenson (2004), pp. 24–25</ref>

==Footnotes==
{{reflist}}

==Sources==
* Атанас Пейчев и колектив, 1300 години на стража, Военно издателство, София 1984.
* Васил Н. Златарски, История на българската държава през средните векове, Част I, II изд., Наука и изкуство, София 1970.
* {{cite book |last=Bakalov | first=Georgi | title=Том 5 от История на българите: Военна история на българите от древността до наши дни| publisher=TRUD Publishers | year= 2003 | isbn= 978-954-621-235-1}}
* {{Warfare, State and Society in the Byzantine World, 565–1204}}
* {{cite book |last=Haldon | first=John | title=The Byzantine Wars | publisher=The History Press | year=2008 }}
* {{cite book|last=Hupchick|first=Dennis|title=The Bulgarian-Byzantine Wars For Early Medieval Balkan Hegemony: Silver-Lined Skulls and Blinded Armies|location=Wilkes-Barre, PA, US|publisher=Palgrave Macmillan|year=2017|isbn=978-3-319-56205-6}}
* John Skylitzes, ''Synopsis Historion'', translated by Paul Stephenson.
* [[Theophanes Continuatus]], ed. Bekker, pp.&nbsp;388–390.
* Йордан Андреев, Милчо Лалков, Българските ханове и царе, Велико Търново, 1996.
* {{cite book |last=Stephenson | first=Paul| title=Byzantium's Balkan Frontier: A Political Study of the Northern Balkans, 900–1204 | publisher=Cambridge University Press | year=2004 | isbn=0-511-03402-4}}

==Further reading==
* {{cite journal |last1=Stoyanov |first1=Aleksandr |title=The Size of Bulgaria's Medieval Field Armies: A Case Study of Military Mobilization Capacity in the Middle Ages |journal=Journal of Military History |date=July 2019 |volume=83 |issue=3 |pages=719–746 |url=https://search.ebscohost.com/login.aspx?direct=true&db=31h&AN=137192875&site=eds-live&scope=site}}

== External links ==
* {{Commons category inline|Battle of Anchialos (917)}}

{{DEFAULTSORT:Achelous 917}}
[[Category:910s conflicts]]
[[Category:910s in the Byzantine Empire]]
[[Category:917]]
[[Category:10th century in Bulgaria]]
[[Category:Military history of Bulgaria]]
[[Category:Battles involving the First Bulgarian Empire]]
[[Category:Battles of the Byzantine–Bulgarian Wars]]
[[Category:Battles of the Hungarian invasions of Europe]]
[[Category:Battles involving Hungary]]
[[Category:Battles involving Hungary in the Middle Ages]]
[[Category:History of Burgas Province]]
[[Category:Pomorie]]