Matthew Poole and continuators on 2 Kings 23:36

36 ¶ Jehoiakim was twenty and five years old when he began to reign , and he reigned eleven years in Jerusalem: and his mothers name was Zebudah, the daughter of Pedaiah of Rumah.

Either, 1. When he began to Reign alone, and with full Power, or after Iehoahaz his Death: till which the people would not disown him whom they had Anointed King, which was esteemed a great tie; 2 Sam. 19. 10. nor own, or accept Iehojakim as their King, but only as his Brothers Vice-roy, though Pharaoh had by violence forced him upon them. And so Iehoahaz might be his Elder Brother, and the same who is called Iohanan, and is first mentioned, as the eldest son, 1 Chron. 3. 15. though he may be placed first, not in regard of his Birth, but of his Dignity; the Crown being first put upon his Head. Or, 2. When he was first set up by Pharaoh, and so this was the Elder Brother, though by popular Violence put by his Right. See on ver. 31.