It was from Manu that all men, including Brahmanas, Kshatriyas and others have been born. O great king, the Brahmanas and Kshatriyas were subsequently united.
ब्रह्मक्षत्रादयस्तस्मान्मनोर्जातास्तु मानवाः। ततोऽभवन्महाराज ब्रह्मक्षत्रेण संगतम्॥