To the west of Esrolia are four Orlanthi tribal confederations. The first – Longsi Land has long been under the suzerainty of the Esrolian Queens. In older texts this was called Haradlaro or the Harandings. Some scholars speculate that this was the homeland of the great Orlanthi hero Aram ya-Udram. It is now a semi-autonomous part of Esrolia.
Further west are the Ditali, who have caused so much trouble for Esrolia in the decade. At the Dawn, the Vathmai came from this area. Although most of the population are Orlanthi clans, the Ditali confederation was traditionally an alliance held together by Trader Princes. However, in the last decade they have cooperated with the Solanthi in raids and invasions of the former Holy Country.
Still further west are the Solanthi. Although once allied to the Trader Princes, for the past generation this confederation has been held together by the household of Greymane, an Orlanthi warlord. The Solanthi and Ditali raided Esrolia for the last decade, then allied with the Esrolians against the Lunar Empire, only to betray the Esrolians at the Battle of Pennel Ford. The confederation is now in disarray after that battle.
Still further west is the Nimistor confederation. These Orlanthi are allied with the Trader Princes, although those alliances have been fraying in the last generation as the Trader Princes have lost much wealth with the Opening.
The Trader Princes traditionally had alliances with otherwise autonomous Orlanthi clans and tribes – that’s the various confederations, each centered on a river network for trade. They are “Princes” in that they are not kings or tribal leaders, but First among equals.That system has been falling apart since the Opening. The Ditali Trader Princes have had to take a more active military role to survive, the Solanthi Trader Princes now must defer to the house of Greymane and his heirs.
So it is the same system as described in the Guide.