The Valakians were one of two humanoid species native to the planet Valakis, the other being the Menk. The Valakians were an endangered species. Their nation, the Commonwealth of Menk and Valakis, became a member of the United Federation of Planets in 2236. (ENT episode: "Dear Doctor", ST reference: Star Charts)
In the 22nd century, they were suffering from a genetic disease which became a planet-wide epidemic. The available data predicted their extinction by the 24th century. Several space shuttles were launched to search for warp-capable species which would assist them. The Valakians made first contact with the Ferengi and the M'klexa, neither of which would solve their medical crisis.
Sometime between September and October 2151, a space shuttle was discovered by the United Earth starship Enterprise (NX-01), who offered their assistance. However, when Doctor Phlox discovered that the Menk, the Valakians' evolutionary counterparts, were evolving, Enterprise left hoping that the Valakians would develop a cure on their own so as not to interfere with the two species' natural evolution. (ENT episode: "Dear Doctor")