Chera-Chola wars of the 11th century CE. The Vempolinadu royal family got evolved into two independent branches by the 12th century CE - the southern branch among them later came to be known as the kingdom of Thekkumkur. It included the modern-day Taluks of Changanassery, Kanjirappally, Kottayam, and Thiruvalla, along with the High Range region of Idukki district. The High Range region was later handed over to the Poonjar dynasty by the Thekkumkur Rajas. The Dutch East India Company was attracted by enormous growth of black pepper in the High Ranges of the Idukki district. According to the treaty signed on 16 June 1664, Dutch Malabar had trade contracts with the Thekkumkur Rajas on spices, cinnamon, opium, etc. The Thekkumkur Rajas allied with the Kingdom of Cochin and the Kingdom of Odanad (Kayamkulam) against the military invasions of the kingdom of Travancore into its northern kingdoms that occurred during the 1740's. As a result, Anizham Thirunal Marthanda Varma, the architect of the modern Travancore, attacked and annexed the kingdom of Thekkumkur into Travancore in 1749 during the Battle of Changanassery, after his annexation of Kayamkulam in 1746. The Thekkumkur king took refuge in the kingdom of the Zamorin of Calicut following his defeat in the battle. Poonjar dynasty (1160-1750 CE) In , Kulothunga Chola, who belonged to the lineage of the Medieval Cholas, entered into a war with Manavikrama Kulasekhara Perumal, who belonged to the Pandya dynasty of Madurai. Upon the failure in the battle, Manavikrama appointed his brother Maravarman Sreevallabha as the monarch of the Pandya dynasty and left Madurai with his family and some of his trusted servants. Manavikrama crossed the Western Ghats and sought political asylum in Kerala. The ruler of Thekkumkur awarded him a portion of the Meenachil taluk which included the region of Poonjar along with the High Range region in the Idukki district in 1160 CE, which originally belonged to the Thekkumkur Rajas. This incident commenced the beginning of the Poonjar dynasty in the region. The territory of Poonjar was annexed by the Kingdom of Travancore following the annexation of the principalities of Thekkumkur and Vadakkumkur in 1749-1750. Travancore Era (1750-1947) Entire portion of the modern-day district of Idukki became part of the erstwhile British Princely state of Travancore by 1750 CE. This era marked considerable progress and social reformation in all spheres. The social development indicators like the literacy rate were improved considerably