The geographical data of the Çatapatha Brahmana point to the land of the Kuru-Panchalas being still the centre of Brahmanical culture. Janamejaya is here celebrated as a king of the Kurus, and the most renowned Brahmanical teacher of the age, Aruni, is expressly stated to have been a Panchala. Nevertheless, it is clear that the Brahmanical system had by this time spread to the countries to the east of Madhyadeça, to Kosala, with its capital, Ayodhya (Oudh), and Videha (Tirhut or Northern Behar), with its capital, Mithila. The court of King Janaka of Videha was thronged with Brahmans from the Kuru-Panchala country. The tournaments of argument which were here held form a prominent feature in the later books of the Çatapatha Brahmana. The hero of these is Yajnavalkya, who, himself a pupil of Aruni, is regarded as the chief spiritual authority in the Brahmana (excepting Books VI.-X.). Certain passages of the Brahmana render it highly probable that Yajnavalkya was a native of Videha. The fact that its leading authority, who thus appears to have belonged to this Eastern country, is represented as vanquishing the most distinguished teachers of the West in argument, points to the redaction of the White Yajurveda having taken place in this eastern region. The Çatapatha Brahmana contains reminiscences of the days when the country of Videha was not as yet Brahmanised. Thus Book I. relates a legend in which three stages in the eastward migration of the Aryans can be clearly distinguished. Mathava, the king of Videgha (the older form of Videha), whose family priest was Gotama Rahugana, was at one time on the Sarasvati. Agni Vaiçvanara (here typical of Brahmanical culture) thence went burning along this earth towards the east, followed by Mathava and his priest, till he came to the river Sadanira (probably the modern Gandak, a tributary running into the Ganges near Patna), which flows from the northern mountain, and which he did not burn over. This river Brahmans did not cross in former times, thinking "it has not been burnt over by Agni Vaiçvanara." At that time the land to the eastward was very uncultivated and marshy, but now many Brahmans are there, and it is highly cultivated, for the Brahmans have caused Agni to taste it through sacrifices. Mathava the Videgha then said to Agni, "Where am I to abide?" "To the east of this river be thy abode," he replied. Even now, the writer adds, this river forms the boundary between the Kosalas (Oudh) and the Videhas (Tirhut). The Vajasaneyi school of the White Yajurveda evidently felt a sense of the superiority of their sacrificial lore, which grew up in these eastern countries. Blame is frequently expressed in the Çatapatha Brahmana of the Adhvaryu priests of the Charaka school. The latter is meant as a comprehensive term embracing the three older schools of the Black Yajurveda, the Kathas, the Kapishthalas, and the Maitrayaniyas.