Berengar I (Latin: Berengarius, Perngarius; Italian: Berengario; c. 845 – 7 April 924[1]) was the king of Italy from 887 and emperor between 915 and his death in 924.

Berengar was a son of Eberhard of Friuli and Gisela, daughter of Louis the Pious and his second wife Judith.

Sometime during his margraviate, he married Bertila, daughter of Suppo II, thus securing an alliance with the powerful Supponid family.

[3] She would later rule alongside him as a consors, a title specifically denoting her informal power and influence, as opposed to a mere coniunx, wife.

[6] With this he obtained a key position in the Carolingian Empire, as the march bordered the Croats and other Slavs who were a constant threat to the Italian peninsula.

[7] When, in 875, the Emperor Louis II, who was also King of Italy, died, having come to terms with Louis the German whereby the German monarch's eldest son, Carloman, would succeed in Italy, Charles the Bald of West Francia invaded the peninsula and had himself crowned king and emperor.

In 883, the newly succeeded Guy III of Spoleto was accused of treason at an imperial synod held at Nonantula late in May.

[11] Berengar and Liutward had a feud that year, which involved his attack on Vercelli and plundering of the bishop's goods.

[13] He made peace with the emperor and compensated for the actions of the previous year by dispensing great gifts.

[17] Charter evidence begins Berengar's reign at Pavia, in the Basilica of San Michele Maggiore,[18] between 26 December 887 and 2 January 888, though this has been disputed.

In Summer 888, Guy, who had failed in his bid to take the West Frankish throne, returned to Italy to gather an army from among the Spoletans and Lombards and oppose Berengar.

This he did, but the battle they fought near Brescia in the fall was a slight victory for Berengar, though his forces were so diminished that he sued for peace nevertheless.

Berengar, in order to prevent a war, sent dignitaries (leading men) ahead to meet Arnulf.

[24] Represented by his counsellor Walfred at the city of Verona, he remained master in Friuli, which was always the base of his support.

As a result, they supported another candidate for the throne, the aforementioned Louis of Provence, another maternal relative of the Carolingians.

In 900, Louis marched into Italy and defeated Berengar; the following year he was crowned Emperor by Pope Benedict IV.

When he broke this oath by invading the peninsula again in 905, Berengar defeated him at Verona, captured him, and ordered him to be blinded on 21 July.

After the siege, Berengar granted the bishop of the city walls and the right to rebuild them with the help of the citizens and the refugees fleeing the Magyars.

In January 915, Pope John X tried to forge an alliance between Berengar and the local Italian rulers in hopes that he could face the Saracen threat in southern Italy.

[37] After the death of the saintly Bishop Stephen in 920, Herman I, Archbishop of Cologne, representing the German interests in Lotharingia, tried to impose his choice of the monks of the local cloister, one Hilduin, on the vacant see.

The clergy opposed to this interference appealed to Berengar, King Charles III of France and Pope John.

By 915, Berengar's elder daughter, Bertha, was abbess of Santa Giulia in Brescia, where her aunt had once been a nun.

[42] His younger daughter, Gisela of Friuli, had married Adalbert I of Ivrea as early as 898 (and no later than 910), but this failed to spark an alliance with the Anscarids.

[53] Some historians have seen his "private defence initiatives" in a more positive light and have found a coherent policy of gift giving.