Part of Arzawa, it was located north of Mira and south of Wilusa, and at one point controlled the island of Lazpa.

According to Mursili, he besieged the Seha River Land's capital and was on the verge of destroying it when he accepted a last minute mercy plea from King Manapa-Tarhunta's own mother, delivered right outside the city gates.

Masturi's ascent to the throne was supported by Mursili's successor Muwatalli II, and the kingdom appears to have remained loyal to the Hittites under his rule.

This revolt was crushed by the Hittite king Tudhaliya IV, after which a descendant of Manapa-Tarhunta was reinstalled on the Seha River Land's throne.

[4] The leading candidate for the site of its capital is Kaymakçı Tepe near the Gediz River, where excavations since 2014 have revealed a major Bronze Age settlement whose citadel is more than four times larger than that of contemporary Troy.