Amba-deva was a 13th-century chief who carved out an independent principality in present-day Andhra Pradesh in southern India. He was a member of the Kayastha family, whose members were vassals to the Kakatiya monarchs. Amba-deva succeeded his elder brother Tripurari as the Kayastha chief in 1272, and soon gave up allegiance to the Kakatiya queen Rudrama. He defeated several Kakatiya subordinates, and also fought against the neighbouring Pandyas and their vassals to carve out an independent principality with its capital at Valluru-pattana. A Kakatiya force sent by Rudrama's successor Prataparudra defeated him in mid-1291.

Amba-deva came from the Kayastha family, who were subordinates to the Kakatiya family. His elder brothers - first Janniga-deva and then Tripurari-deva (alias Tripurantaka) - preceded him as Kayastha chiefs. In the early 1260s, the neighbouring Pandyas captured the southern part of the Kakatiya kingdom. The 1264 CE and 1269 CE inscriptions of Janniga-deva suggest that he re-established the Kakatiya power in this area. Janniga-deva's successor Tripurari also remained loyal to Rudrama, and ruled as her subordinate during 1270–1272.

According to Janniga-deva's inscriptions, he ruled the area extending from Panugal in the north to Kaivaram-kota in the south; the Kakatiya monarch Ganapati had conferred this area as a fief upon him. However, epigraphic evidence suggests that the Kalukada chiefs - Keshava-deva and his brother Raya-murari Soma-deva - controlled much of this area.

Amba-deva succeeded his brother Tripurari-deva as the Kayastha chief in 1272 CE, and remained in that position for 32 years. He appears to have been loyal to the Kakatiya monarch Rudrama for some time, as suggested by his title raya-sthapanacharya ("a pillar of support for the kingdom"). However, his inscriptions do not mention any overlord, which suggests that he soon asserted independence, giving up his allegiance to the Kakatiya queen Rudrama. It is not clear what circumstances led him to this decision.

Ambadeva's 1290 CE Tripurantakam inscription, written in Sanskrit language, records his military successes, including his victories over the feudatories (mandalikas) of Rudrama. The chronology of these victories is not certain, but can be determined to some degree with the help of other contemporary records.

According to the Tripurantakam inscription, in 1273, Amba-deva defeated the Kakatiya vassal Shripati Ganapati, the ruler of the Gurindala (Gurazala or Gurijala) area, and assumed Ganapati's title Raya sahasra-malla.

Ganapati's rule over the Gurindala area is attested by his 1268 Mutukur inscription, and by Amba-deva's Nilagangavaram inscription, which calls him Gurindala Ganapati.

Another inscription, engraved on the same stone as Ganapati's Mutukur inscription on the same day, states that the local Vira Balanja community made a gift to a village temple on behalf of Rudrama. This suggests that Ganapati was a vassal of Rudrama. It is not clear what circumstances led to her conflict with Amba-deva.