Coligny (French pronunciation: [kɔliɲi]; Arpitan: Colignê) is a commune in the Ain department in eastern France.

The commune lies near Bourg-en-Bresse; the Solnan forms its southwestern border.

This lunisolar calendar, which dates from second-century Roman Gaul, has been key in the understanding of the knowledge of astronomy among the Gauls and also supplied interesting information about the Gaulish language, such as the names of months and the words for "lucky" and "unlucky."

[3] It is written in the Latin alphabet and it represents a five-year cycle composed of three years having twelve lunar months and two years (the first and third) having thirteen lunar months.

Lexicographer and poet Marie-Marguerite Brun (1713–1794) was born in Coligny.