Henry II (German: Heinrich II; Italian: Enrico II; Latin: Henricus; 6 May 973 – 13 July 1024), also known as Saint Henry, Obl. S. B., was Holy Roman Emperor (Latin: Romanorum Imperator) from 1014. He died without an heir in 1024, and was the last ruler of the Ottonian line. As Duke of Bavaria, appointed in 995, Henry became King of the Romans (Latin: Rex Romanorum) following the sudden death of his second cousin, Emperor Otto III in 1002, was made King of Italy (Latin: Rex Italiae) in 1004, and crowned emperor by Pope Benedict VIII in 1014.

The son of Henry II, Duke of Bavaria, and his wife Gisela of Burgundy, Emperor Henry II was a great-grandson of German king Henry the Fowler and a member of the Bavarian branch of the Ottonian dynasty. Since his father had rebelled against two previous emperors, the younger Henry spent long periods of time in exile, where he turned to Christianity at an early age, first finding refuge with the Bishop of Freising and later during his education at the cathedral school in Hildesheim. He succeeded his father as Duke of Bavaria in 995 as Henry IV. As duke, he attempted to join his second-cousin, Emperor Otto III, in suppressing a revolt against imperial rule in Italy in 1002. Before Henry II could arrive, however, Otto III died of fever, leaving no heir. After defeating several contenders to the throne, Henry II was crowned King of Germany on 9 July 1002 as the first in a line of kings to adopt the title Rex Romanorum as an antedate to his coronation in Rome as Imperator Romanorum. On 15 May 1004, he was anointed King of Italy (Rex Italiae). In that same year, Henry II joined Duke Jaromír of Bohemia in his struggle against the Poles, thus effectively incorporating the Duchy of Bohemia into the Holy Roman Empire.

Unlike his predecessor Otto III, who had imposed plans on sovereign administration and active political involvement in Italy, Henry spent most of his reign concerned with the renovation ("renewal") of the imperial territories north of the Alps, a policy summed up on his seal as Renovatio regni Francorum, which replaced Otto's Renovatio imperii Romanorum. A series of conflicts with the Polish Duke Bolesław I, who had already conquered a number of countries surrounding him, required Henry II's full attention and years of political and military maneuvering. Henry did, however, lead three expeditions into Italy to enforce his feudal claim (Honor Imperii): twice to suppress secessionist revolts and once to address Byzantine attempts to obtain dominance over southern Italy. On 14 February 1014, Pope Benedict VIII crowned Henry Holy Roman Emperor in Rome.

The rule of Henry II has been characterized as a period of centralized authority throughout the Holy Roman Empire. He consolidated his power by cultivating personal and political ties with the Catholic Church. He greatly expanded the Ottonian dynasty's custom of employing clerics as counter-weights against secular nobles. Through donations to the Church and the establishment of new dioceses, Henry strengthened imperial rule across the Empire and increased control over ecclesiastical affairs. He stressed service to the Church and promoted monastic reform. For his remarkable personal piety and enthusiastic promotion of the Church, he was canonized by Pope Eugene III in 1146. He is the only medieval German monarch ever to have been honoured as a saint. Henry II's wife was the equally pious Empress Cunigunde, who was canonized in 1200 by Pope Innocent III. As the union produced no children, the German nobles elected Conrad II, a great-great-grandson of Emperor Otto I, to succeed him after his death in 1024. Conrad was the first of the Salian dynasty of emperors.

Henry was born in May 973, the son of Duke Henry II of Bavaria, and Gisela of Burgundy. Through his father, he was the grandson of Duke Henry I of Bavaria, and the great-grandson of King Henry I of Germany. By his mother, he was the grandson of King Conrad I of Burgundy, and the great-grandson of King Rudolf II of Burgundy.

The elder Henry came into conflict with his cousin Holy Roman Emperor Otto II, in 974. The elder Henry and Otto II disputed each other's claims to authority over the Duchy of Swabia: Henry claimed the duchy as his birthright while Otto II maintained his right to name a duke of his choosing. After an initial failed revolt, Otto II imprisoned the elder Henry in Ingelheim. After escaping, Henry again revolted against Otto II. When this second revolt failed, Otto II deposed Henry as Duke of Bavaria and sent him into exile under the custody of the Bishop of Utrecht in April 978. As a consequence of his revolt, the Emperor stripped the Duchy of Bavaria of its southeastern territories bordering Italy and formed the Duchy of Carinthia.

During his father's exile, the younger Henry lived in Hildesheim. As a child he was educated in the Christian faith by Bishop Wolfgang of Regensburg, and then studied at the Hildesheim Cathedral. The Emperor himself ensured the younger Henry received an ecclesiastical education in order that by becoming a religious official he would be prevented from participating in the Imperial government.

The death of Otto II in 983 allowed the elder Henry to be released from custody and to return from exile. The elder Henry claimed regency over Otto III, the three-year-old child of Otto II. After a failed attempt to claim the German throne for himself in 985, the elder Henry relinquished the regency to the child's mother Theophanu. In return for his submission to the child king, Henry was restored as Duke of Bavaria. The younger Henry, now thirteen years old, was named his regent over Bavaria. When the elder Henry died in 995, the younger Henry was elected by the Bavarian nobles as the new duke to succeed his father.