kingdom · Italy

Kingdom of Cottius

58 BCE – 63 CE (approx.) · capital Segusio

Alpine client kingdom around Susa whose ruler Cottius allied with Augustus and gave his name to the Cottian Alps.

Origins

In the 1st century BCE the Segusini and neighbouring Alpine peoples around the Mont Genèvre pass were ruled by a king named Donnus, who appears in Caesar's time. His son, Marcus Julius Cottius, chose to make peace with Augustus rather than resist the Roman conquest of the Alps.

Rule and society

Cottius governed fourteen Alpine communities as a Roman prefect while keeping royal status locally. He built and maintained the road over the Mont Genèvre pass, a key route between Italy and Gaul. In 9–8 BCE he erected the Arch of Augustus at Segusio (Susa), whose inscription lists his peoples. The kingdom combined Celtic traditions with Roman administration.

Decline and legacy

Claudius restored the royal title to Cottius's son, Marcus Julius Cottius II, in 44 CE. When he died without an heir around 63 CE, Nero annexed the kingdom as the province of the Alpes Cottiae. The name survives in the Cottian Alps.

Lineage

Kingdom of CottiusRoman Empire 27 BCE – 476 CE

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Cite this page
APA
The Epoch Institute. (2026). Kingdom of Cottius. In The Epoch Institute States Register. https://the-epoch-institute.org/state/kingdom-of-cottius
MLA
“Kingdom of Cottius.” The Epoch Institute States Register, The Epoch Institute, 2026, https://the-epoch-institute.org/state/kingdom-of-cottius. Accessed .
Chicago
The Epoch Institute. “Kingdom of Cottius.” The Epoch Institute States Register. 2026. https://the-epoch-institute.org/state/kingdom-of-cottius.
Harvard
The Epoch Institute (2026) ‘Kingdom of Cottius’, The Epoch Institute States Register. Available at: https://the-epoch-institute.org/state/kingdom-of-cottius (Accessed: ).

Last reviewed October 2026Random state ↻