Alaric I (Gothic: Alareiks - "supreme chief/ruler"; Latin: Alaricus; 370 (or 375) – 410 AD) was the first King of the Visigoths from 395–410, son (or paternal grandson) of chieftain Rothestes. Alaric is best known for his sack of Rome in 410, which marked a decisive event in the decline of the Roman Empire.
Alaric began his career under the Gothic soldier Gainas and later joined the Roman army. Alaric's first appearance was as the leader of a mixed band of Goths and allied peoples who invaded Thrace in 391 and were stopped by the half-Vandal Roman General Stilicho. In 394 he led a Gothic force of 20,000 that helped the Eastern Roman Emperor Theodosius defeat the Frankish usurper Arbogast at the Battle of Frigidus. Despite sacrificing around 10,000 of his men, Alaric received little recognition from the Emperor. Disappointed, he left the army and was elected reiks of the Visigoths in 395, and marched toward Constantinople until he was diverted by Roman forces. He then moved southward into Greece, where he sacked Piraeus (the port of Athens) and destroyed Corinth, Megara, Argos, and Sparta. As a response, the Eastern emperor Flavius Arcadius appointed Alaric magister militum ("master of the soldiers") in Illyricum.
In 401 Alaric invaded Italy, but he was defeated by Stilicho at Pollentia (modern Pollenza) on April 6, 402. A second invasion that same year also ended in defeat at the Battle of Verona, though Alaric forced the Roman Senate to pay a large subsidy to the Visigoths. During Radagaisus' Italian invasion in 406, Alaric remained idle in Illyria. In 408, Western Emperor Flavius Honorius ordered the execution of Stilicho and his family, amid rumours that the general had made a deal with Alaric. Honorius then incited the Roman population to massacre tens of thousands of wives and children of foederati Goths serving in the Roman military. Subsequently, around 30,000 Gothic soldiers defected to Alaric, and joined his march on Rome to avenge their murdered families.
Moving swiftly along Roman roads, Alaric sacked the cities of Aquileia and Cremona and ravaged the lands along the Adriatic Sea. The Visigothic leader thereupon laid siege to Rome in 408. Eventually, the Senate granted him a substantial subsidy. In addition, Alaric forced the Senate to liberate all 40,000 Gothic slaves in Rome. Honorius, however, refused to appoint Alaric as the commander of the Western Roman Army, and in 409 the Visigoths again surrounded Rome. Alaric lifted his blockade after proclaiming Attalus Western Emperor. Attalus appointed him magister utriusque militiae ("master of both services") but refused to allow him to send an army into Africa. Negotiations with Honorius broke down, and Alaric deposed Attalus in the summer of 410, and besieged Rome for the third time. Allies within the capital opened the gates for him on August 24, and for three days his troops sacked the city. Although the Visigoths plundered Rome, they treated its inhabitants humanely and burned only a few buildings. Having abandoned a plan to occupy Sicily and North Africa after the destruction of his fleet in a storm, Alaric died as the Visigoths were marching northward.