Nizamabad was founded in the year 1905 when Nizam's Dominion were recognized, where up to it was known as Indur.The Nizam of Hyderabad ruled over the Deccan region during the 18th century.
Nizamabad was a part of princely State of Hyderabad in 1724 and continued to be part of the Nizam's dominions until 1948. After India gained independence in 1947, the Indian Armed Forces annexed Hyderabad and ended the rule of the Nizam in Operation Polo. It was during 1876 Nizamabad became a separate district when the districts in Hyderabad State were reorganized by Salar Jung-I, the then prime minister. In 1905 the railway line between Secunderabad and Manmad was laid. The city was named after Nizam ul Mulk, the fourth Nizam of Hyderabad state. And during the reign of last Nizam, Nizam Sagar dam was constructed in 1923 across the Manjira River at the village of Achampet which irrigates 250,000 acres (1,000 km2; 390 sq mi) of land in Nizamabad District.[source:wiki]