Simplon was the name of a department of the First French Empire. It is named after the Simplon Pass. It was formed in 1810, when the Rhodanic Republic was occupied by the French. Its territory corresponded with that of the present Swiss canton of Valais. The capital of Simplon was Sion. The department was subdivided into the following arrondissements and cantons (situation in 1812):
- Sion, cantons: Hérémence, Leuk (French: Loèche), Sierre and Sion.
- Brig, cantons: Brig, Goms (French: Conches), Mörel, Raron and Visp (French: Viège).
- Saint-Maurice, cantons: Entremont, Martigny, Monthey and Saint-Maurice.
Its population in 1812 was 65,500, and its area was approximately 500,000 hectares.
After the final defeat of Napoleon Bonaparte in 1815, the department became the Swiss canton of Valais.
Coordinates: 46°14′00″N 7°22′00″E / 46.2333°N 7.36667°E