Otto III (June, 980 - January 23, 1002) was Holy Roman Emperor from 996 to his death in 1002. A member of the Ottonian dynasty, Otto III was the only son of Emperor Otto II and Theophanu.

Otto III was crowned King of Germany in 983 at age of three shortly after his father's death in southern Italy while campaigning against the Byzantine Empire and the Muslim Emirate of Sicily. Though the nominal ruler of Germany, Otto III's minor status ensured his various regents held power over the Empire. His cousin Henry II, Duke of Bavaria, initially claimed regency over the young king and attempted to seize the throne for himself in 984. When his rebellion failed to gain the support of Germany's aristocracy, Henry II was forced to abandon his claims to the throne and to allow Otto III's mother Theophanu, who would serve as regent until 991. Still only a child, Otto III's grandmother, the Dowager Empress Adelaide of Italy, served as regent until Otto III reached adulthood in 994.

In 996, Otto III marched to Italy to claim the titles King of Italy and Emperor which had been left unclaimed since Otto II's death in 983. Otto III also sought to reestablish Imperial control over the city of Rome, which had revolted under the leadership of Crescentius II, and through it the papacy. Crowned as Emperor, Otto III put down the Roman rebellion and installed his cousin as the Pope Gregory V, the first Pope of German descent. After pardoning him and leaving the city, Crescentius II again rebelled against the Emperor, deposing Gregory V and installing John XVI as Pope. Otto III returned to the city in 998, reinstalled Gregory V, and executed both Crescentius II and John XVI. When Gregory V died in 999, Otto III installed Sylvester II as the new Pope. Otto III's actions throughout his life further strengthened Imperial control over the Catholic Church.

For the beginning of his reign, Otto III faced opposition from the Slavic peoples along Germany's eastern border. Following the death of his father in 983, the Slavs rebelled against Imperial control, forcing the Empire to abandon its territories east of the Elbe river. Otto III would fight to regain the Empire's lost territories throughout his reign with only limited success. While in the east, Otto III strengthened the Empire's relations with Poland, Bohemia, and Hungary. Through his affairs in Eastern Europe in 1000, Otto III was able to extend the influence of Christianity by supporting mission work in Poland and through the crowning of Stephen I as the first Christian king of Hungary.

Returning to Rome in 1001, Otto III faced a rebellion from the Roman aristocracy which forced him to flee the city. While marching to reclaim the city in 1002, however, Otto III suffered a sudden fever and died in a castle near Civita Castellana at the age of 21. With no clear heir to succeed him, his early death threw the Empire into political crisis.

Otto III was born in June or July 980 somewhere between Aachen and Nijmegen (modern day North Rhine-Westphalia). The only son of Emperor Otto II and his wife Theophanu, Otto III was the youngest of the couple's four children. Immediately prior to Otto III's birth, his father had completed military campaigns in France against King Lothar.

On July 14, 982, Otto II's army suffered a crushing defeated against the Muslim Emirate of Sicily at the battle of Stilo. Otto II had been campaigning in southern Italy with hopes of annexing the whole of Italy into the Holy Roman Empire. Otto II himself escaped the battle unharmed but many important imperial officials were among the battle's casualties. Following the defeat and at the insistence of the Empire's nobles, Otto II called an assembly of the Reichstag in Verona on Pentecost in 983. Otto II proposed to the assembly to have the three-year-old Otto III "elected" King of Germany, becoming Otto II's clear heir apparent. This was the first time a German ruler was elected on Italian soil. When the assembly was concluded, Otto III and his mother Theophanu travelled across the Alps in order for Otto III to receive his coronation at Aachen, the traditional site for the coronation of the German kings. Otto II stayed behind to address military action against the Muslims. While still in central Italy, however, Otto II suddenly died on November 7, 983, and was buried in St. Peter's Basilica in Rome.

Otto III was crowned as king on Christmas Day in 983, three weeks after his father's death. Otto III was crowned by Willigis, the Archbishop of Mainz, and John, the Archbishop of Ravenna. News of Otto II's death first reached Germany shortly after Otto III's coronation.The unresolved problems in southern Italy and the Slavic uprising on the Empire's eastern border made the Empire's political situation extremely unstable. With a minor on the throne, the Empire was thrown into confusion, with Otto III's mother Theophanu assuming the role of regent for her young son.

Death

After having summoned his army in late 1001, Otto III headed south to Rome to ensuring his rule over the city. During the travel south, however, Otto III suffered a sudden and severe fever. He died in a castle near Civita Castellana on January 24, 1002. He was 21 years old and had reigned as an independent ruler for just under six years, having nominally reigned for under 19 years. The Byzantine princess Zoe, second daughter of Emperor Constantine VIII) had just disembarked in Puglia, on her way to marry him. Otto III's death has been attributed to various causes. Medieval sources speak of malaria, which he had caught in the unhealthy marshes that surrounded Ravenna. Following his death, the Roman people suggested that Stefania, the widow of Crescentius II, had made Otto III fall in love with her and then poisoned him.

The Emperor's body was carried back to Germany by his soldiers, as all the while his route was lined with Italians who hurled abuses at his remains. He was buried in Aachen Cathedral alongside the body of Charlemagne.

Succession crisis

Otto III, having never married, died without any child, leaving the Empire without a clear successor. As the funeral procession moved through the Duchy of Bavaria in February 1002, Otto III's cousin Henry IV, son of Henry II and the new Duke of Bavaria, asked the bishops and nobles to elect him as the new king of Germany. With the exception of the Bishop of Augsburg, Henry IV received no support for his claims. At Otto III's funeral on Easter, 1002, in Aachen, the German nobles repeated their opposition to Henry IV. Several rival candidates for the throne - Count Ezzo of Lotharingia, Margrave Eckard I of Meissen, and Duke Herman II of Swabia - strongly contested Henry IV's succession,

Without an Emperor on the throne, Italy began to break away from German control. On February 15, 1002, the Lombard Margrave of Ivrea Arduin, an opponent of the Ottonian dynasty, was elected King of Italy in Pavia.