In January 1750 Marthanda Varma of Travancore laid his crown, umbrella, fans and sword with tulsi leaves on the stone step before Padmanabhaswamy, signed the kingdom over to the god, and took the sword back as the god's servant.
Marthanda Varma had made Travancore by force: he had broken the nobles who opposed him and beaten the Dutch at Colachel. Then he rebuilt Padmanabhaswamy's temple and set a single great slab of stone, the Ottakkal Mandapam, in front of the reclining god. On the fifth of Makaram in the Kollam year 925, January 1750, he came to the temple with his family, his Dewan Ramayyan Dalawa and the temple council, laid on that stone the crown, the royal umbrella, the two white fans and his sword with a handful of tulsi, and signed a deed giving the god all the land between the Thovala fort in the east and the Kavana river in the west, to last as long as the sun and moon. The priest handed the sword back. From that day the king ruled as Padmanabhadasa, the servant of Padmanabha, and every king after him took the title, down to Sree Chithira Thirunal.
Sources: Thrippati Danam: a ritual by which the rulers of Travancore became Padmanabhadasas (Hindupost); Thrippadidanam (Malayalam Wikipedia); Padmanabhaswamy Temple (Encyclopaedia Britannica)