The famous 'Calcutta Stone', dating from A.D. 1041, describes a terrible calamity which befell the East Javanese kingdom of Isana in the early years of the 11th century. A rebellion incited by a jealous vassal king resulted in the destruction of the capital of Watugaluh. The reigning king, Dharmawangsa, successor to Sri Makutawangsawardhana, was murdered along with his entire family. Only the young Airlangga, who was aged about 16 at the time, managed to escape unharmed.
After spending three or four years in the safety of a forest retreat, Airlangga, as the closest surviving relative to Dharmawangsa, emerged to take over the throne in about 1020. The early part of his reign was spent putting down rebellions and securing the borders of his kingdom. Among his successful military campaigns were those against King Wishnuprabhawa of Wuratan, King Wijaya of Wengker, as well as the subjugation of a powerful queen in the south. In 1032 Airlangga attacked and defeated the ruler of Wurawari, who is believed to have been responsible for the earlier destruction of the old capital of Isana.By the end of Airlangga's reign, in the mid 11th century, the kingdom which he had established is believed to have stretched from Pasuruan in the east, to present day Madiun in the west.
Although there are few surviving archaeological remains dating from his time, Airlangga is known to have been a keen patron of the arts, notably literature. In around 1035, the court poet Mpu Kanwa produced the Arjuna Wiwaha, which has to this day remained one of Java's most popular classical stories. Adapted from the Indian Mahabharata epic, the poem recounts episodes in the life of the hero sage Arjuna, who was an incarnation of the Hindu god Wishnu. There are reasons to believe that the poem was a portrait of the life of Airlangga himself. He, like Arjuna, was seen as a divine incarnation, apparently laid to rest at Candi Belahan, where he was portrayed in stone as Wishnu on Garuda.
Towards the end of his life, Airlangga was faced with the problem of succession. The rightful heir, the princess Sanggramawijaya, refused the throne, preferring to live her life as a hermit. She is traditionally associated with the legend of Dewi Kilisuci and the cave of Selomangleng at Kediri.
Airlangga's realm was, as a result, eventually divided between two of his sons, giving rise to the separate kingdoms of Janggala and Kediri. It was Kediri, however, which was to become the dominant power until the rise of Singosari in the early 13th century.