Tessic's colony was a deuterium-mining colony of Tessic's species. For five seasons, a group of Klingon marauders lead by Korok harassed the mining colony, taking the majority of the deuterium and leaving only the bare minimum so the colony could survive.
In 2152, the Earth starship Enterprise NX-01 arrived at the colony to obtain deuterium thereby becoming aware of the situation. The ship's crew taught the colony how to defend itself, ambushing Korok and his men and eventually driving them off. (ENT: "Marauders")