Manthara (Sanskrit: मन्थरा; lit: "humpbacked") in the Hindu epic Ramayana convinced Queen Kaikeyi that the throne of maharaja belonged to her son Bharata and that her step-son—crown-prince Rama (the hero of the Ramayana)—should be exiled from the kingdom. She was like a mother figure to Kaikeyi and her twin Yuddhajit, for their mother was banished. She accompanied Kaikeyi to Ayodhya after her marriage to Dasharatha.
As family servant of Kaikeyi, Manthara lived with her from the time of her birth. When she hears that King Dasharatha is planning to make his eldest son, Rama, prince regent (rather than Bharata, his child by Kaikeyi), she flies into a rage and reports the news to Kaikeyi. Kaikeyi is initially pleased and hands Manthara a pearl necklace.
Manthara reminds Kaikeyi of the two boons Dasharatha had given her when she had once saved his life in a celestial battle. Kaikeyi had kept these boons for later and Manthara declares that this is the right time to ask for them. She advises Kaikeyi to lie in her room wearing soiled clothes and no ornaments. She should weep and cry, pretending anger. When Dasharatha would come to console her, she should immediately ask for the boons. The first boon would be that Bharata would be made the king. The second boon would be that Rama should be sent into the forest for exile for fourteen years. Manthara reckons that the fourteen-year banishment would be long enough for Bharata to consolidate his position in the Empire and weave his way into people's hearts.
Manthara appears only once in the Ramayana after Rama's banishment. Having been rewarded by Kaikeyi with costly clothing and jewels, she is walking in the palace gardens when Bharata and his half-brother Shatrughna come upon her. Seeing her, Shatrughna flies into a violent rage over Rama's banishment and assaults her murderously. Kaikeyi begs Bharata to save her, telling Shatrughna that it is a sin to kill a woman and that Rama would be furious with them both if he does such a thing. He relents and the brothers leave, while Kaikeyi attempts to comfort Manthara.
When Rama came to Ayodhya with Sita and Lakshmana after 14 years of exile, Rama was made the king of Ayodhya. After coronation of Rama, Rama and Sita gifted jewels and clothes to their servants. Than, Rama asked Kaikeyi that where is Mantahra. Then, Kaikeyi is told that Manthara is very sorry for her act and for 14 years she has been waiting for Rama to apologize to him. Rama went to a dark room where Manthara was lying on the floor. Seeing Lakshmana, Sita and Rama, she apologized for her treachery and Rama forgave her.