The different branches of Vedic literature had grown out of one another.
The four Vedas were followed by the Brahmanas, the Aranyakas, and the Upanishads.
The Brahmanas explain in detail various Vedic sacrificial ceremonies and their origins. It is the earliest of the Aryan's prose literature.
The Aranyakas contains the philosophical and mystical content. They are called so because their contents required that they should be studied in the isolation of the forest (aranya). They are the closing portions of the Brahmanas.
In the last phase of the Vedic literature, Upanishads were deduced form the tradition of the Aranyakas.
The Rig Veda deals with Karmakanda (ritualistic) and philosophical aspects.
The Brahmanas contains the ritualistic aspect.
The Upanishads contains the philosophic aspect.
Chhandogya and Brihadaranyaka are the two oldest and most important of forms of the Upanishads.
Other important Upanishads include Kathak, Isa, Mundaka, Prasna, etc.
The main settlement of the Rig Vedic people was the region of Indus and Saraswati Valleys. However, during the later Vedic period, Samhitas and Brahmanas mentions that the settlements covered virtually the whole of northern India.
The Ganga river, by the time, occupied the proud place of the most revered and sacred river of India. Therefore, the center of civilization now shifted from Saraswati to Ganga.
There was remarkable development in gradual expansion and consolidation of Vis.
Jana known in Rig Vedic period like Bharatas, Purus, Tritsus, and Turvasas were slowly merging with other Janas and disappeared from the scene. People of Anus, Druhyus, Turvasas, the Krivis, were also vanished.
The states, namely Kasi, Kosala, Videha, Magadha, and Anga developed in the eastern Uttar Pradesh and Bihar. However, the areas of south India are not clearly mentioned.
The struggle for supremacy among different states was of frequent occurrence. The ideal of universal empire appeared.
Satapatha Brahmana mentioned the expansion of people towards the east. It mentioned Videgh Madhav migrated from the land of Vedic Culture (Saraswati Valley) and crossed Sadanira (modern Gandak River) and the eastern boundary of Kosala and came to the land of Videha (modern Tirhut).
The growth of three kingdoms, namely Kosala, Kasi, and Videha took place. Thereafter, the excavations at Hastinapur, Atranjikhera, and many other sites have revealed cultures ranging from 2,000 B.C. onwards.
Some characteristic of the pottery of post Harappan period were noticed as Ochre Colored Pottery (O.C.P.) (c. 2,000-1,500) and during c. 1,200-600 B.C., Black and Red ware, Painted Grey Ware etc. were noticed.
Northern Black Polished (N.B.P.) ware came to be manufactured about 7th century B.C.
The Kuru-Panchala region is mentioned in the Upanishads as the seat of culture and prosperity. It was the region of present western and central Uttar Pradesh.
Three kingdoms of Kosala, Kasi, and Videha mentioned as the seats of Vedic culture.
Magadha and Anga were also mentioned as distant lands in the Atharvanaveda.
In the south, Vidarbha (in Maharashtra) was mentioned.
The states of Bahlikas, Kesins, Kekayas, and Kamboja were situated in the further west to Punjab.
With the growing concept of states, kingship became the normal form of government. The kingship was being given the status of divine origin.
Terms like adhiraj, rajadhiraja, samrat, and ekrat were used in most of the text refers to the concept of a king of kings.
The term ekrat defined in Atharvanaveda, refers the paramount sovereign.
Special ceremonies were organized for the appointment of kings, such as the Vajpeya, Rajsuya, and Ashvamedha.
The monarchy was established on the firm foundations. It was not absolute, but limited in several ways.
Certain democratic elements were operating within the framework of kingship. These were −
The people's right in choosing their king;
The conditions imposed on king's rights and duties;
The kings dependence on the council of his ministers; and
The assemblies of people, sabha, and samiti, as check upon king's absolutism.
The king, under no circumstances, be considered as the sole owner of the kingdom with absolute power over the objects and subjects.
The king was holding the kingdom as a trust. He was supposed to be only a trustee and hold it on the condition that he would promote the people's well-beings and progress.
Sabha and Samiti played important role in the administration along with the ministers and officials,
The sabha functioned as a parliament for disposal of public business by debate and discussion.
The Chief of the sabha was called as the sabhapati, the keepers as sabhapala and the members as sabheya, sabhasad, or sabhasina
Rules were framed to govern the debate in sabha.
Sabha also acted as a court of justice as it is said that "one who attends the Sabha sits as a law court to dispense dharma Justice".
Samiti was the larger General Assembly of the people and it was different than Sabha in terms of function and composition. The Sabha was a smaller selected body, which functioned as the lower court.
Due to increase in complexity of the society and political structure, some new officials were appointed by the state namely −
Bhagadugha (collector of taxes),
Gramini (head of a village),
Sthapati (chief judge),
Kshatri (chamberlain), etc.
The administrative machinery was highly organized and became an efficient instrument for ruling over a large kingdom.
Legal institutions became more focused. The king administered justice and wielded the rod of punishment.
Petty offences were left to "village judges.”
The punishments for the crime were rather severe.
For evidence, the eye-witness was more important than informer.
The law was also very clear on the question of inheritance of property, ownership of land, etc.
The father's property was inherited by sons alone.
The daughters could inherit it only if she was the only child or there were no male issues.