The Algebraist by Iain Banks

It is 4034 AD. Humanity has made it to the stars. Fassin Taak, a Slow Seer at the Court of the Nasqueron Dwellers, will be fortunate if he makes it to the end of the year. The Nasqueron Dwellers inhabit a gas giant on the outskirts of the galaxy, in a system awaiting its wormhole connection to the rest of civilization. In the meantime, they are dismissed as decadents living in a state of highly developed barbarism, hoarding data without order, hunting their own young and fighting pointless formal wars.