Rajendra I (/rɑːdʒeɪndrə/; Middle Tamil: Rājēntira Cōḻaṉ; Classical Sanskrit: Rājēndradēva Cōla; Old Malay: Raja Chulan; c. 971 CE – 1044 CE), who is often referred to as Rajendra the Great and Gangaikonda Cholan (Middle Tamil: Kaṅkaikoṇṭa Cōḻaṉ; Bringer of the Ganges), and Kadaram Kondan (Middle Tamil: Kaṭāram Koṇṭāṉ; Conqueror of Kedah), was a Chola Emperor who reigned from 1014 and 1044 CE. He was born in Thanjavur to Rajaraja I and his queen Vanathi and assumed royal power as co-regent with his father in 1012 until his father died in 1014, when Rajendra ascended to the Chola throne. During his reign, the Chola Empire reached its zenith in the Indian subcontinent; it extended its reach via trade and conquest across the Indian Ocean, making Rajendra one of only a few Indian monarchs who conquered territory beyond South Asia.
In his early years, Rajendra was involved in the Chola Army, with which he fought in several campaigns against the Western Chalukyas and the rulers of Anuradhapura, earning him his first victories. He quelled rebellions in the Chera and Pandiya vassal states, and in Sri Lanka. As Emperor, Rajendra completed the conquest of Anuradhapura and brought a large portion of Sri Lanka under imperial rule. Rajendra expanded Chola rule by defeating the kingdoms of Kalinga and Vengai, and subduing the islands of Laccadives and the Maldives, which he renamed Munnir Palantivu Pannirayiram ("Twelve Thousand Islands and the Ocean Where Three Waters Meet"). These islands were later used as strategic naval bases. During his South-East Asia campaign, he annexed Srivijaya, Kedah, Tambralinga and Pegu, achieving imperial dominance in the region and strengthening Indian influence in Southeast Asia.
Rajendra conducted a war against the Pala dynasty and captured a great deal of wealth, which he used to build the city of Gangaikondacholapuram, the capital of the Chola Empire, and one of the centres of trade and commerce in the empire for several centuries.