In Hinduism, Itihasa-Purana, also called the fifth Veda, refers to the traditional accounts of cosmogony, myths, royal genealogies of the lunar dynasty and solar dynasty, and legendary past events, as narrated in the Itihasa (Mahabharata and the Ramayana) and the Puranas. They are highly influential in Indian culture, and many classical Indian poets derive the plots of their poetry and drama from the Itihasa. The Epic-Puranic chronology derived from the Itihasa-Puranais an influential frame of reference in traditional Indian thought.

Itihāsa, इतिहास, derived from the phrase iti ha āsa इति ह आस, which means "so indeed it was".

Puranas, /pʊˈrɑːnə/; Sanskrit: पुराण, purāṇa literally means "ancient, old."

Itihasa refers to the Sanskrit Epics of the Mahabharata and the Ramayana. The Puranas are a vast genre of Hindu literature about a wide range of topics, particularly about cosmogony, myths, legends and purported history. Together they are also called the fifth Veda, "the Holy Book of the masses who were not entitled to study the four Vedas."

The tradition of Itihāsa is generally understood to be developed by the bardic tradition of Sūtas and Cāraṇas whose duties consisted of composing royal eulogies.

In the mythical narratives of the Itihasa-Purana there is no clear distinction between mythology, hagiography and historiography. The Indian tradition regards the Itihasa-Purana as authoritative historical writings, documenting past events and prescribing dharma, the right way to live. The Itihasa-Purana forms the basis for the Epic-Puranic chronology, the traditional timeline of legendary history. The Mahabharata includes the story of the Kurukshetra War and preserves the traditions of the Lunar dynasty in the form of embedded tales. The Ramayana contains the story of Rama and is incidentally related to the legends of the Solar dynasty. The Puranas provide the idea of yugas and the Dashavatara, the ten incarnations of Vishnu in the four respective yugas.

According to the Hindu texts, time is cyclic. The history of mankind is divided into four ages—Satya Yuga, Treta Yuga, Dvapara Yuga and Kali Yuga—collectively forming one Maha Yuga. Seventy-one Maha Yugas form a Manvantara ("age of Manu"), a period of time over which a "Manu" presides. For the duration of his period, each Manu is the archetypal first man, the progenitor of humanity, and also the first king and lawgiver. Along with a Manu, every Manvantara also has its own set of Indra, gods and the seven sages. Fourteen Manus reign in Kalpa, (a single day in the life of) Brahma), an equivalent of 1,000 Maha Yugas, at the end of which, the creation is destroyed and is followed by a Pralaya (dissolution) of equal length. The creation starts again, in the next Kalpa in an endless cycle of creations and dissolutions.

The Dashavatara refers to the ten primary (i.e. full or complete) incarnations (avatars) of Vishnu, the Hindu god of preservation which has Rigvedic origins. Vishnu is said to descend in the form of an avatar to restore cosmic order. The word Dashavatara derives from daśa, meaning "ten", and avatar (avatāra), roughly equivalent to "incarnation".