And some notes on the background and a couple of the worlds:
The Olazabal subsector is one of eight subsectors entirely owned by the Euskal Herria - an interstellar confederacy founded by Basque colonists. The Olazabal subsector is considered something of a backwater, but it is one of the longest settled areas of Euskal Herria space and thus has strong emotional ties for most Basques. Its mapping and planetary surveyance was carried out by three explorers - Olazabal, Urzaiz and Arzalluz - who are considered among the greatest of all Basque spacefarers, though they all died some 8,000 years ago.
The Euskal Herria takes a lassez-faire approach to planetary rule, and directly governs only three worlds in all of the twelve subsectors where it has a presence. All the worlds in the Olazabal subsector have complete autonomy and are required only to submit 0.5% of their Gross Domestic Product in taxes to the central authority. However, the Herria brooks no attempt at complete secession and has shown itself willing to attack and occupy worlds which attempt to declare complete independence.
An earth-sized world with an atmosphere of argon and an average temperature well over boiling. It is named after the first Basque in space, who entered earth orbit in 2008. The large population live in subterranean tunnel systems with life support provided by technicians from the Euskara Herria. This is more than worth their while: Eyharts is one of the biggest producers of precious metals in the sector, though its distance from regular communication and trade routes means that freight is infrequent. There are three governments on the planet - one technocracy (the major polity), a military junta, and a slave-owning oligarchy. All three are hostile to one another, though open warfare is infrequent. Eyharts' distance from other systems and the unusual situation in which its inhabitants live has caused eccentric cultural developments: the inhabitants use sex to seal trade agreements and reproduce with cloning.
Santurtzi is the food-producing hub of the subsector, and the dominant power is a Soviet-style Communist bureaucracy where the population inhabit communal farms. Its huge port, from which many of the surrounding systems are fed, houses the main Euskal Herria consulate in its region of space. Two minor regions of the planet have independence from the Santurtzi state - one is a tiny representative democracy, the other a throwback to hereditary kingship. Trade on Santurtzi is governed by a complex set of rules based on citizens' social class (actual or percieved).
Irun declared independence from the Euskal Herria twenty years ago; it has since been invaded by the main fleet in the subsector and a naval base set up, amid rumours of massacre and repression. All travel to the system is forbidden and its UWP is based on old and unconfirmable data.
Uzcudun is a water world, its entire surface one unbroken ocean. Its handful of inhabitants live in raft-like dwellings and have a nomadic existence sailing along age-old lines of migration, though their advanced technology allows them to remain in constant communication. One of their notable traditions is the deliberate blinding of their family elders, in an elaborate ritualistic ceremony. Despite its tiny population Uzcudun has one of the largest space ports in the subsector (built, at considerable expense, on a platform anchored to the ocean floor) and a Euskal Herria consulate; it is a tourist hub for the elite of the entire Euskal sector.
A poor, rocky world with a climate similar to earth's arctic circle and a small, rabidly xenophobic population living in nomadic clan groups. Cabbarus is also a notable hideout for pirates, smugglers and outcasts, with a Traveller's Aid Society well known to be corrupted beyond all usefulness and a middle-sized but delapidated space port. Over the centuries the Euskal Herria has attempted on several occasions to occupy the planet and install a 'responsible government', but the cost of doing so - in men and resources - has always proved prohibitive, especially given Cabbarus' utter poverty.