and began writing royal proclamations in the local language. During the next fifty years, Telugu inscriptions appeared in Anantapuram and other neighbouring regions. The Madras Museum plates of Balliya-Choda dated to the mid-ninth century CE are the earliest copper plate grants in the Telugu language. Certain exploration and excavation missions conducted by the Archaeological Department in and around the Keesaragutta temple have brought to light, a number of brick temples, cells and other structures encompassed by brick prakaram along with coins, beads, stucco figures, garbhapatra, pottery, and Brahmi label inscriptions datable to 4th and 5th centuries CE. On top of one of the rock-cut caves, an early Telugu label inscription reading as 'Thulachuvanru' can be noticed. On the basis of palaeography, the inscription is dated around the 4th to 5th centuries CE. Telugu was more influenced by Sanskrit and Prakrit during this period, which corresponded to the advent of Telugu literature. Telugu literature was initially found in inscriptions and poetry in the courts of the rulers, and later in written works such as Nannayya's Mahabharatam (1022 CE). During the time of Nannayya, the literary language diverged from the popular language. It was also a period of phonetic changes in the spoken language. Middle Ages The third phase is marked by further stylization and sophistication of the literary languages. During this period the split of the Telugu from Kannada alphabets took place. Tikkana wrote his works in this script. Vijayanagara Empire The Vijayanagara Empire gained dominance from 1336 to the late 17th century, reaching its peak during the rule of Krishnadevaraya in the 16th century, when Telugu literature experienced what is considered its Golden Age. Delhi Sultanate and Mughal influence A distinct dialect developed in present-day Telangana region, due to Persian/Arabic influence: the Delhi Sultanate of the Tughlaq dynasty was established earlier in the northern Deccan Plateau during the 14th century. In the latter half of the 17th century, the Mughal Empire extended further south, culminating in the establishment of the Hyderabad State by the dynasty of the Nizam of Hyderabad in 1724. This heralded an era of Persian influence on the Telugu language, especially Hyderabad State. The effect is also evident in the prose of the early 19th century, as in the kaifiyats. In the princely Hyderabad State, the Andhra Mahasabha was started in 1921 with the main intention of promoting Telugu language, literature, its books and historical research led