The Caucasus region was indeed part of the Soviet Union from 1922 to 1991. This mountainous area straddles Eastern Europe and Western Asia, bordered by the Black Sea to the west and the Caspian Sea to the east. It encompasses several republics that were part of the Soviet Socialist Republics:

1. Georgian Soviet Socialist Republic
2. Azerbaijan Soviet Socialist Republic
3. Armenian Soviet Socialist Republic

These three republics gained independence when the Soviet Union dissolved in 1991. Each had its own unique culture, languages, and histories within the larger Soviet framework.

Some key points about the Caucasus region during Soviet times:

- The region was known for its ethnic diversity, with many different groups including Georgians, Armenians, Azerbaijanis, Chechens, Ingush, Ossetians, and others.
- It was an important area for agriculture, particularly tea and citrus production.
- The region had significant oil and natural gas resources.
- There were conflicts and tensions between various ethnic groups, some of which continue to this day.
- The city of Sochi in the North Caucasus was developed as a resort town during Soviet times.

The Soviet era had a major impact on the development, politics, and cultures of the Caucasus republics, shaping them in ways that continue to influence the region today.