Majorian (Latin: Julius Valerius Maiorianus; c. 420 – 7 August 461) was the western Roman emperor from 457 to 461. A prominent general of the Roman army, Majorian deposed Emperor Avitus in 457 and succeeded him. Majorian was the last emperor to make a concerted effort to restore the Western Roman Empire with its own forces. Possessing little more than Italy, Dalmatia, and some territory in northern Gaul, Majorian campaigned rigorously for three years against the Empire's enemies. His successors until the fall of the Empire, in 476/480, were actually instruments of their barbarian generals, or emperors chosen and controlled by the Eastern Roman court.

After defeating a Vandal attack on Italy, Majorian launched a campaign against the Visigothic Kingdom in southern Gaul. Defeating king Theodoric II at the Battle of Arelate, Majorian forced the Goths to abandon their possessions in Septimania and Hispania and return to federate status. Majorian then attacked the Burgundian Kingdom, defeating them at the Siege of Lugdunum, expelling them from the Rhone valley and reducing them to federate status.

In 460, Majorian left Gaul to consolidate his hold on Hispania. His generals launched a campaign against the Suebic Kingdom in northwest Hispania, defeating them at the battles of Lucus Augusti and Scallabis and reducing them to federate status as well. His fleet for his planned campaign to recover Africa from the Vandals was destroyed due to treachery.

Majorian sought to reform the imperial administration in order to make it more efficient and just. The powerful general Ricimer deposed and killed Majorian, who had become unpopular with the senatorial aristocracy because of his reforms.

To historian Edward Gibbon, Majorian "presents the welcome discovery of a great and heroic character, such as sometimes arise, in a degenerate age, to vindicate the honour of the human species".