Nikephoros undertook a comprehensive reorganisation of the Byzantine Empire and made efforts to strengthen its borders. Similarly to the Isaurian emperors, Nikephoros enacted a vigorous policy of resettlement of impoverished soldiers and peasants from the
themes of
Asia Minor to
Thrace,
Macedonia,
Epirus,
Thessaly and southern
Greece. He expanded and consolidated the imperial military forces in various themes, managing the empire's finances with strict discipline, which led to the displeasure and hostility of his subjects. To secure political stability and succession, he crowned his son
Staurakios co-emperor on Christmas Day 803. According to later accounts by
Theophanes Continuatus in the 10th century and
Synopsis Chronike in the 13th century, the rebellion of General
Bardanes Tourkos in 803 may have been triggered by dissatisfaction with Nikephoros' handling of army salaries. Two influential supporters of Bardanes, Generals
Leo (later Emperor Leo V) and
Michael (later Emperor Michael II), defected to Nikephoros, receiving major promotions as a reward. Bardanes surrendered on the condition of a pledge of safety for him and his followers but he was soon blinded and sent to a
monastery. A conspiracy led by the patrician
Arsaber in 808 had a similar outcome. In 805, the
Sclaveni of
Patras in the
Peloponnese rebelled against Nikephoros, who in response appropriated them and their property to the
Archbishopric of Patras. Upon the death of Patriarch
Tarasios of Constantinople in February 806, Nikephoros appointed an
iconodule layman,
Nikephoros, causing the monks at the
Monastery of Stoudios including
Theodore the Stoudite and
Plato of Sakkoudion to grow hostile towards him. Nikephoros also revived the
Moechian controversy by convoking a synod in which
Constantine VI's second marriage was declared lawful. Theodore persuaded his brother, Joseph, the
Archbishop of Thessalonica, to refuse to celebrate the Christmas liturgy with the Patriarch and Emperor, leading to a confrontation. Nikephoros confirmed in a 809 synod that the emperor was not bound by
canon law, and demoted Joseph, Theodore and Plato, banishing them to the
Princes' Islands. Although the Stoudites were unsuccessful, Theodore's subsequent reputation benefited from his position and behaviour. Nikephoros' imposition of taxes and his attempts to exert control over the church created a rift between him and the clergy. Although he appointed the iconodule Nikephoros as the
patriarch, Emperor Nikephoros was portrayed unfavorably by ecclesiastical historians such as
Theophanes the Confessor.
Italy In 802,
Charlemagne recognised the
Republic of Venice as a
Frankish fief under his third son,
Pepin of Italy. Nikephoros responded by sending a fleet, but a compromise was reached in which the pro-Frankish
Doge,
Obelerio degli Antenori, would accept the additional title of
spatharios to confirm his imperial loyalty. Nikephoros concluded a treaty known as the "
Pax Nicephori" with Charlemagne, but refused to acknowledge his imperial status. Relations between the two deteriorated, leading to a war over Venice between 807 and 810 when Obelerio began to show signs of disloyalty, and a second Byzantine fleet arrived. While Nikephoros managed to suppress a rebellion in Venice in 807, he suffered significant losses to the Franks. The conflict was ultimately resolved after Nikephoros' death. Local opinion was overwhelmingly in favour of Byzantium, resulting in the assignment of Venice,
Istria, the
Dalmatian coast, and
Southern Italy to the Eastern realm, while
Rome,
Ravenna, and the
Pentapolis were included in the Western realm.
Campaigns against the Arabs and Bulgars captures Nikephoros I, from the 14th-century
Manasses Chronicle. Shortly after Nikephoros' accession, he sent an insulting letter to
Abbasid Caliph Harun al-Rashid, demanding the return of tribute which Empress Irene had paid. He withheld further tribute, and there may have been raids against Arab settlements. Nikephoros thus committed himself to a war against Harun. Due to Bardanes' disloyalty, Nikephoros was forced to lead the military campaign himself, resulting in a severe defeat at the
Battle of Krasos in Phrygia in 805. Although there was an exchange of prisoners, Harun imposed a tribute of 30,000
dinars on Byzantium. In 806, a Muslim army comprising 135,000 soldiers
invaded the Empire, once again led by Harun, and captured
Heraclea Cybistra and
Tyana. Unable to match the Muslim forces, Nikephoros agreed to peace on the condition of an immediate payment of 50,000
nomismata and an annual tribute of 30,000
nomismata. Harun had taken measures to secure the Arab-Byzantine frontier including the construction of new fortified districts (
al-Awasim) in order to more effectively gain control of
Asia Minor. However, with the Caliphate embroiled in a
succession struggle following Harun al-Rashid's death in 809, Nikephoros was able to focus on dealing with
Krum, the Khan of Bulgaria, who was posing a threat to the empire's northern frontiers and had recently conquered
Serdica (now
Sofia). Irene abolished several economic policies enacted by the Isaurians to sustain the Byzantine military, including the taxing of soldiers' widows to compensate for the loss of a fully-equipped soldier, if their household were to continue receiving a pension and tax exemptions. Thus, there was a manpower shortage by 809/810 which forced Nikephoros to decree that rural peasants be enlisted and equipped at the expense of their fellow villagers—a policy which drew harsh criticism from
Theophanes the Confessor who numbered it among Nikephoros' "vexations". In 809, near the river
Struma, the Bulgars captured the wagon of the
rogai (cash remuneration for the Byzantine military), which contained 79,200
nomismata. In 811, the Arabs captured the
rogai of the
Armeniac Theme which totalled to 93,600
nomismata. The payment of
rogai was vital for the military and so the wagon was a key target for enemy capture. In 811, Nikephoros launched an invasion of
Bulgaria and was initially successful against Khan Krum and his armies, and sacked the Bulgarian capital,
Pliska. The
Chronicle of
Michael the Syrian, a 12th-century patriarch of the Syrian Jacobites, describes the brutality and atrocities committed by Nikephoros: "Now Nicephorus went with a large force against the Bulghars. He reached the capital city of their kingdom and caused great destruction, to the point that he threw their little children on the ground and mercilessly drove over them with his threshing wagons." As Nikephoros' forces were returning to Byzantium, the imperial army was ambushed and annihilated in the
Varbitsa Pass at the
Battle of Pliska by Krum. Nikephoros perished in the battle, and Krum is said to have had his head severed and used his skull as
a drinking cup. The defeat was disastrous for Byzantine morale and for the political stability of the Empire. ==Assessment and legacy==