Ataulf was king of the Visigoths from 410 to 415. The modern historian of the Goths

Goths

The Goths were an East Germanic tribe of Scandinavian origin whose two branches, the Visigoths and the Ostrogoths, played an important role in the fall of the Roman Empire and the emergence of Medieval Europe....

, Herwig Wolfram, summarizes the last seven years of his life, the only ones that we can follow: "within that period he developed from a tribal chief to a late antique statesman."
He was unanimously elected to the throne to succeed his brother-in-law Alaric

Alaric I

Alaric I was the King of the Visigoths from 395–410. Alaric is most famous for his sack of Rome in 410, which marked a decisive event in the decline of the Roman Empire....

, who had been struck down by a fever suddenly in Calabria

Calabria

Calabria , in antiquity known as Bruttium, is a region in southern Italy, south of Naples, located at the "toe" of the Italian Peninsula. The capital city of Calabria is Catanzaro....

. King Ataulf's first act was to halt Alaric's southward expansion of the Goths in Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

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Meanwhile, Gaul

Gaul

Gaul was a region of Western Europe during the Iron Age and Roman era, encompassing present day France, Luxembourg and Belgium, most of Switzerland, the western part of Northern Italy, as well as the parts of the Netherlands and Germany on the left bank of the Rhine. The Gauls were the speakers of...

 had been separated from the western Roman Empire

Roman Empire

The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....

 by the usurper Constantine III

Constantine III (usurper)

Flavius Claudius Constantinus, known in English as Constantine III was a Roman general who declared himself Western Roman Emperor in Britannia in 407 and established himself in Gaul. Recognised by the Emperor Honorius in 409, collapsing support and military setbacks saw him abdicate in 411...

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