saḥ that, kākutstha: descendant of the Kakutsthas (Rama), tadā then, svābhiḥ his own, prakṛtibhiḥ by the subjects, yācyamānaḥ although pleaded, pitaram father's, satyam as truthful, kurvāṇaḥ doing, vanamēva to the forest, anvapadyata proceeded.
Although entreated by his subjects (not to go) Rama proceeded to the forest to make his father's vow come true.