Because of drinking the breast milk of their mother, the nine sons of Āgnīdhra naturally had strong, well-built bodies. Their father gave them each a kingdom in a different part of Jambūdvīpa. The kingdoms were named according to the names of the sons. Thus the sons of Āgnīdhra ruled the kingdoms they received from their father.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
आग्नीध्रसुतास्ते मातुरनुग्रहादौत्पत्तिकेनैव संहननबलोपेताः पित्रा विभक्ता आत्मतुल्यनामानि यथाभागं जम्बूद्वीपवर्षाणि बुभुजुः
āgnīdhrasutāste māturanugrahādautpattikenaiva saṃhananabalopetāḥ pitrā vibhaktā ātmatulyanāmāni yathābhāgaṃ jambūdvīpavarṣāṇi bubhujuḥ
SB 5.2.21