The Gzilt were a sort of cousin species/civilisation to the Culture. Nearly founders, though not quite, they had been influential in the setting up and design of the Culture almost ten thousand years earlier, when a disparate group of humanoid species at roughly the same stage of technological and societal development had been thinking about banding together.
Amiable enough, if somewhat martially uptight due to an unusual social set-up that basically meant everybody was presumed to be in a single society-wide militia – hence everybody had a military rank, from birth – they had made significant contributions to the establishment and ethos of the Culture while it was all still at the being-talked-about phase but then, almost at the last moment, and to pretty much everyone’s surprise, in a way including their own, they had decided not to join the new confederation. They’d go their own way, they’d decided, wishing the Culture well and taking an interest in it, but keeping determinedly apart from it.
Relations had remained friendly throughout, and rumours persisted that the Gzilt had been helpful to the Culture in the Idiran war, despite a supposedly meticulous neutrality, but in essence they had stayed quietly, studiously apart from the Culture for all that time, observing the more rowdy, boisterous and interference-minded behaviour of their one-time associates with a mixture of emotions that might on occasion have included mild horror, gasping incredulity and simple shock, but also – and more consistently – a kind of envy, and a slowly increasing feeling that a great opportunity had been lost.
- Hydrogen Sonata, Chapter Five: (S -22)