Śatapatha Brāhmaṇa ("of a hundred paths") 9.4.1.1

9.4.1.1

athāto rāṣṭrabhṛto juhoti | rājāno vai rāṣṭrabhṛtaste hi rāṣṭrāṇi bibhratyetā ha devatāḥ sutā etena savena yenaitatsoṣyamāṇo bhavati tā evaitatprīṇāti tā asmā iṣṭāḥ prītā etaṃ savamanumanyante tābhiranumataḥ sūyate yasmai vai rājāno rājyamanumanyante sa rājā bhavati na sa yasmai na tadyadrājāno rāṣṭrāṇi bibhrati rājāna u ete devāstasmādetā rāṣṭrabhṛtaḥ

He then offers the Râshtrabhrit (realm-sustaining) oblations;--the realm-sustainers, doubtless, are the kings, for it is they that sustain realms. These deities, indeed, have been consecrated by this same consecration ceremony by which he (the Sacrificer) is now to be consecrated: it is them he thereby gratifies, and thus gratified by offering, they grant him permission (to perform) this consecration ceremony, and, permitted by them, he is consecrated; for only he becomes king whom the (other) kings allow (to assume) the royal dignity, but not he whom they do not (allow to assume it). And inasmuch as the kings sustain realms, and these gods are kings, therefore Realm-sustaining (oblations are performed).