The Mahabharata is one of the two major Sanskrit epics of ancient India. It is an epic narrative of the Kurukshetra War and the fates of the Kauravas and the Pandava princes as well as containing philosophical and devotional material, such as a discussion of the four goals of life.
Here we have Anusasana Parva, the fourteenth, also known as the Book of the Horse Sacrifice consists of the narration about the royal ceremony of the Ashvamedha conducted by Yudhisthir. Yudhisthir was filled with joy when he heard from Arjuna about his great deeds upon his return to Kingdom of Hastinapur after his world conquest. All the defeated kings and those who accepted the sovereignty of Yudhisthir over their kingdom presented themselves in the Horse Sacrifice in Hastinapur.
Vyasa is a revered figure in Hindu traditions. He is a kala-Avatar or part-incarnation of God Vishnu. Vyasa is sometimes conflated by some Vaishnavas with Badarayana, the compiler of the Vedanta Sutras and considered to be one of the seven Chiranjivins. He is also the fourth member of the Rishi Parampara of the Advaita Guru Parampara of which Adi Shankara is the chief proponent.