Shodai-sama no Kikan: Shijou Saikyou ga 1000-nengo no Shison ni Tensei Suru

Story

Gilphas Eldragon, the founding patriarch of the Eldragon family, dedicated his entire life to the pursuit of absolute strength. In search of eternal combat, he consumed a legendary fruit rumored to grant immortality under the protection of the divine dragon. Yet the rumor was false—Gilphas aged, and in the end, passed away in his son’s arms. Or so it seemed. When he next opened his eyes, Gilphas found himself reborn a thousand years later as Zeke Eldragon, heir to his own bloodline.

Synopsis via AniList (English).