Bolarus IX (also known as simply Bolarus, Bolius IX, or Bolias) was the inhabited ninth planet in its star system. This planet was the homeworld of the Bolians, a warp-capable humanoid species. It was located in the Bolian sector of the Alpha Quadrant. (TNG: "Allegiance"; DS9: "The Forsaken"; VOY: "Unity", "In the Flesh")
During the Dominion War (2373-75), the Bolian front was a major area of conflict and important to the defense of the Federation. This may have been centered on the Bolian homeworld, or the Bolian sector. (DS9: "Penumbra")
This planet was only mentioned in dialogue.
According to Star Trek: Star Charts (p. 56 & 66) and Stellar Cartography: The Starfleet Reference Library ("Stellar Cartography" pp. 14-15; "Dominion War: Strategy and Battles, 2373-75"), Bolarus IX orbited a Class B star. This system was threatened by the Dominion from an occupied Benzar between 2374 and 2375.
Like the Bolian species, the Cliffs of Bole were named after director Cliff Bole; however their location has never been specified in a canon production. (Star Trek Encyclopedia (4th ed., vol. 1, p. 146))
The Starfleet Operations Manual describes Bolarus IX as the ninth planet in the system of the subgiant blue star Bolarus (β). It is stormy and oceanic, situated close to the Romulan Neutral Zone. Due to its location, it became a theatre of conflict during the Dominion War.
The novels A Time to Kill and Articles of the Federation state that former Federation President Min Zife (β) was from Bolarus, first serving as planetary district representative, then as Bolian Federation councilor, and finally as president. The councilor representing Bolarus during the novels' timeframe (2379/2380) was Nea (β).