Ajilon Prime was the inhabited prime planet in its star system. This planet was located near the Federation-Klingon border. In the 24th century, this planet was home to a Federation colony with several settlements. The colonial government was partially administrated by Resource. The planet was located "three days at best" from Deep Space 9.
In early 2373, the planet was attacked by the Klingons during the Federation-Klingon War, breaking the cease fire that was initiated a few weeks earlier. In the ensuing Battle of Ajilon Prime, the Klingon forces were quickly able to capture two settlements in the northern hemisphere, trap over half the colonists on the planet and then advance further. During the battle, colonists were evacuated to a base on Tananda Bay by Resource.
Reinforcements were dispatched aboard the USS Farragut, but the vessel was destroyed before reaching the planet. The USS Defiant reached the planet two days later, and Klingon forces pulled out following the reinstatement of the ceasefire. (DS9: "Nor the Battle to the Strong")
Species on the planet
"AZH-zha-lawn" was the pronunciation for this planet's name from the script pronunciation guide.
The planet model for Ajilon Prime was first used for the Ennis/Nol-Ennis moon in "Battle Lines". It was used again for a Cardassian moon in "Improbable Cause" and "Treachery, Faith and the Great River" and the Teplan homeworld in "The Quickening". It was later used for Koralis III in "Chimera" and Sappora VII in "Prodigal Daughter".
According to Star Trek: Star Charts (p. 61) and the Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), Ajilon was an F-class star.