[1] After a series of civil wars during the reign of his father, Louis the Pious, Charles succeeded, by the Treaty of Verdun (843), in acquiring the western third of the empire.

The attempts made by Louis the Pious to assign Charles a subkingdom, first Alemannia and then the country between the Meuse and the Pyrenees (in 832, after the rising of Pepin I of Aquitaine) were unsuccessful.

The settlement gave Charles the Bald the kingdom of the West Franks, which he had been governing until then, and which practically corresponded with what is now France, as far as the Meuse, the Saône, and the Rhône, with the addition of the Spanish March as far as the Ebro.

[9] Charles led various expeditions against the invaders and, by the Edict of Pistres of 864, made the army more mobile by providing for a cavalry element, the predecessor of the French chivalry so famous during the next 600 years.

[13] In 871–872, Charles sent two letters to Pope Hadrian II where he made a defence of royal sovereignty in the face of intrusive actions by the papacy into state affairs.

[14] In 875, after the death of the Emperor Louis II (son of his half-brother Lothair), Charles the Bald, supported by Pope John VIII, traveled to Italy, receiving the royal crown at Pavia and the imperial insignia in Rome on 25 December.

[15][9] As emperor, Charles combined the mottoes that had been used by his grandfather and father into a single formula: renovatio imperii Romani et Francorum, "renewal of the empire of the Romans and Franks".

Charles again crossed the Alps, but this expedition was received with little enthusiasm by the nobles, and even by his regent in Lombardy, Boso, and they refused to join his army.

Charles, ill and in great distress, started on his way back to Gaul, but died while crossing the pass of Mont Cenis at Brides-les-Bains, on 6 October 877.

[17][18][9] According to the Annals of St-Bertin, Charles was hastily buried at the abbey of Nantua, Burgundy, because the bearers were unable to withstand the stench of his decaying body.

Charles was a prince of education and letters, a friend of the church, and conscious of the support he could find in the episcopate against his unruly nobles, for he chose his councillors from among the higher clergy, as in the case of Guenelon of Sens, who betrayed him, and of Hincmar of Reims.