Simhavishnu (IAST: Siṃhaviṣṇu) also known as Avanisimha son of Simhavarman III and one of the Pallava kings of India, was responsible for the revival of the Pallavan dynasty. He was the first Pallava monarch whose domain extended beyond Kanchipuram (Kanchi) in the South. He was portrayed as a great conqueror in Mattavilasa Prahasana (drunken revelry), a drama written by his son Mahendravarman I.
Sailendra Nath Sen 575-600 AD.
T.V. Mahalingam 575–615 CE.
KAN Sastri 555–590 CE.
He ruled at least for 33 years based on the available Hero stones. However, there is no exact consensus as to Simhavishnu's period on the throne.
When Simhavishnu ascended the throne, the Pallava dynasty was beginning to reassert its supremacy.
The southern peninsula of India was then ruled by five dynasties. The Pallavas, the Cholas and the Pandyas shared the power in Tamil Nadu, Andhra Pradesh, parts of southern and eastern Karnataka border and Ceylon; the Cheras controlled Kerala and the Chalukyas controlled Karnataka. Simhavishnu, who was known for his gallant martial courage and judicial wisdom from a young age, overthrew the Kalabhras and conquered the region up to Kaveri, where he came into conflict with the Pandyas and Ceylon. He dispatched a naval expedition and occupied Malaya and Sri Lanka and established Kanchipuram as his capital. The presence of the Pallavas, much before further naval expeditions to Indo-China by their illustrious succeeding and contemporary empires such as the Pandiyans and the Cholas, is attested by the existence of specimen of art bearing striking resemblance in countries like Thailand, Laos, Cambodia, as well as scores of inscriptions in those lands in the Grantha script (a script in which both Tamil and Sanskrit can be written) in which the Pallavas were the first to specialize.
Simhavishnu led the revival of the Pallavas, and the period starting with him came to be known as the Greater Pallavas or Later Pallavas dynasty. The great struggle between the Pallavas and the Chalukyas, which would last for more than two centuries, began during the reign of Simhavishnu.