Battle of Petroe The Battle of Petroe , also known as the Battle of Hades , was fought on August 20 , 1057 between the Byzantine imperial forces of Theodore , the Domestic of the Schools of the East , and the rebellious general Isaac I Komnenos , commander of the Byzantine field army in Anatolia . Komnenos had rebelled against Michael VI Stratiotikos ( r . 1056 – 1057 ) and won over the allegiance of many leading generals , including Nikephoros Bryennios and Nikephoros III Botaneiates . After Komnenos was proclaimed emperor , the two armies clashed at Hades , near the city of Nicaea . Although the right wing of the army of Komnenos was routed , the left wing of Komnenos ’ s army , led by Katakalon Kekaumenos , routed the imperial right , reached and entered their camp , and destroyed the tents . Komnenos himself held firm in the centre , causing the imperial army to break and run , leaving the way open to Constantinople . Background . The short reign of Michael VI Stratiotikos was plagued by internal dissension , as the new emperor proceeded to alienate the leading figures of the military aristocracy . Of the two most important , Katakalon Kekaumenos and Nikephoros Bryennios , Kekaumenos was the most popular general in the empire and the emperor ’ s decision to deprive him of his command at Antioch on charges of extortion did not sit well with the other leading nobles . But it was the emperor ’ s actions towards Nikephoros Bryennios that precipitated the rebellion . His decision to restore Bryennios ’ s rank but not his estates or fortune confiscated by the empress Theodora , and insulting Bryennios to his face when he complained to Michael VI in person proved to be his undoing . Michael VI compounded his error by rebuffing Bryennios after he had already ordered the restored general to lead a division of 3 , 000 men to reinforce the army in Cappadocia . From here Bryennios began plotting to overthrow the emperor . On his arrival however , he attacked and beat a representative of the emperor who countermanded Nikephoros ' s orders before throwing him in prison , which his officers took as a sign that Nikephoros was about to rebel . Releasing the imprisoned officer , they captured Nikephoros , blinded him and sent him to Constantinople . It was Bryennios ' capture that precipitated the military nobility to rally around Isaac Komnenos . Fearing that their plot was about to be discovered , Isaac Komnenos was taken , apparently most unwillingly , by Romanos Skleros , Michael Bourtzes , Nikephoros Botaneiates and the sons of Romanos III Argyros to Gounaria where he was proclaimed emperor on 8 June 1057 . Initial moves . After Isaac Komnenos was raised to the purple , Kekaumenos forged an imperial order ordering him to march against the Seljuk chieftain Samouch with five " tagmata " . Of these , two were Frankish , one Russian , and two were Byzantine – those of Koloneia and Chaldia . Gathering his forces in the plain of Nikopolis , he joined up with what local troops Komnenos was able to gather , crossed the Sangarius river and took possession of Nicaea . The Emperor Michael placed the imperial army under the command of Theodore , a court bureaucrat and eunuch who had been raised to the rank of Domestic of the Schools of the East . With him went the Bulgarian prince Aaron , the brother - in - law of Isaac Komnenos . Together they destroyed the bridges over the Sangarius River , hoping to cut off all communication for the rebel army from the provinces in which they had considerable family influence . From here they began approaching the city of Nicaea . Isaac Komnenos was about 2 kilometres north of the city , and soon the two armies came into contact with each other . After some attempts were made to encourage the opposing armies to defect to the other , Komnenos ordered the ceasing of all communications between the two armies . Theodore , believing this to be a sign of weakness , advanced to Petroe , some 2 . 5 kilometres from Komnenos ’ s camp . The battle . On August 20 , 1057 , Isaac Komnenos drew out his forces and arranged them for battle at a plain called , according to Michael Attaleiates , Polemon or Haidos . Kekaumenos commanded the left wing , Romanos Skleros the right , and Komnenos positioned himself in the centre . On the imperial side , Prince Aaron was stationed on the left wing , Basil Tarchaneiotes was positioned on the right , and the centre was commanded by Theodore the Eunuch . The battle itself was a game of two halves . The imperial left wing under Prince Aaron completely routed the rebel right wing . Pursuing their troops to the rebel camp , he proceeded to capture Romanos Skleros and was on the cusp of victory when he hesitated , unsure of his next move . Komnenos , on the verge of fleeing to Nicaea , was able to catch his breath and review what was happening on his left . There , Kekaumenos had proceeded to rout the imperial Macedonian right , reaching and entering their camp , destroying the tents and killing the imperial generals Maurokatakalos and Katzamountes . This encouraged their own side while sowing doubt in the mind of Prince Aaron and his men . Isaac Komnenos managed to hold the centre firm long enough for Kekaumenos to join him and press in on Theodore . Here the battle was at its thickest , and Komnenos just managed to avoid being killed when he was attacked by four Russians . Eventually , however , the imperial centre began to give way and the imperial troops began fleeing the field . An important commander of the imperial forces , Radulph the Frank , was caught up in the ensuing rout when he caught a glimpse of Nikephoros Botaneiates leading an attacking division . Shouting a war cry , Radulph turned around and proceeded to attack Botaneiates , and the two engaged in single combat until Radulph ’ s sword broke and he was captured . Theodore and Prince Aaron fled to Constantinople , while Isaac Komnenos advanced to Nicomedia . Aftermath . While at Nicomedia , Komnenos was met by envoys of the emperor , including Michael Psellos who offered him the title of Caesar if he would cease his rebellion . Although his proposals were publicly rejected , privately Isaac showed himself more open to negotiation , and he was promised the status of co - emperor . However , during the course of these secret negotiations , a riot in favor of Isaac broke out in Constantinople . The patriarch Michael Keroularios convinced Michael VI to abdicate in Isaac ' s favor on August 31 , 1057 .