Once a year, The Convocation happens on Zefir. Zefir is not considered a part of any of the Seven Cities at the same time it is considered a part of all the Seven Cities. The Empire is currently based out of Zefir. Zefir is an island, and it is known for the strange and often wondrous city that covers the southern third of it and is built to house the leaders of each major Realm as well as retinues of up to 150.
All the leaders of the Seven Cities attend the Convocation – it is rumored they are driven to do so by Powers — and the goal of all of it is Diplomacy. This is helped immensely by the consistent threat the Dread provides.
For fifty years, the Empire has been a product of the Convocation, with standards and agreements being reached among all of them, and with each realm having its own input. The convocation is overseen by the Emperor, whose voice in matters is no greater or lesser than anyone else’s, as he is treated during it as the leader of Sibola, and nothing more.
About 25 years ago, both Kahokia and Hyboria sent representatives, but they do not have voting power. Antilia is considered a rebel province and is barred. It is said that the Exilian showed up the last two years, and are being considered for participation, but again, no voting or say in the proceedings.
The majority of Diplomacy, both warm and cold, is undertaken by Envoys. Envoys are retainers who are trained in the courtly arts and other skills and occupy a place of semi-neutrality, serving as ambassadors and intelligence gatherers (among other things).
Every Court has several, and most Guilds, influential nobles, and even wealthy merchants will employ or make use of an Envoy at some time in some way – or at the least will employ a Messenger.
Envoys may or may not come from a noble background, and may or may not be seen as Courtiers, but they are always present, and always watching, and always listening.