Cognomen Gulain (Gulain 
) , all over the world, is an extremely rare family name. The cognomen Gulain is characteristic of France, where it is an extremely rare surname, India, and the United States. Much more prevalently, Gulain is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gulain | India, France, Democratic Republic of the Congo, United States |