During the life of Svayambhuva Manu, Yajna became the leader of the demigods, Indra

Expressions researched:
"Yajna became the king of the demigods" |"Yajna personally took the post of Indra"

SB Canto 4

During the time of Svāyambhuva Manu, Yajña, being the incarnation of the Supreme Personality of Godhead, became the leader of the demigods, Indra.

SB 4.1.8, Translation and Purport: During the time of Svāyambhuva Manu, these sons all became the demigods collectively named the Tuṣitas. Marīci became the head of the seven ṛṣis, and Yajña became the king of the demigods, Indra. During the life of Svāyambhuva Manu, six kinds of living entities were generated from the demigods known as the Tuṣitas, from the sages headed by Marīci, and from descendants of Yajña, king of the demigods, and all of them expanded their progeny to observe the order of the Lord to fill the universe with living entities. These six kinds of living entities are known as manus, devas, manu-putras, aṁśāvatāras, sureśvaras and ṛṣis. Yajña, being the incarnation of the Supreme Personality of Godhead, became the leader of the demigods, Indra.

SB Canto 8

Yajña personally took the post of Indra, the King of the heavenly planets.

SB 8.1 Summary: The first Manu was Svāyambhuva Manu. His two daughters, namely Ākūti and Devahūti, gave birth to two sons, named Yajña and Kapila respectively. Because Śukadeva Gosvāmī had already described the activities of Kapila in the Third Canto, he now described the activities of Yajña. The original Manu, along with his wife, Śatarūpā, went into the forest to practice austerities on the bank of the River Sunandā. They practiced austerities for a hundred years, and then Manu, in a trance, formed prayers to the Supreme Personality of Godhead. Rākṣasas and asuras then attempted to devour him, but Yajña, accompanied by his sons the Yāmas and the demigods, killed them. Then Yajña personally took the post of Indra, the King of the heavenly planets.