Agramahishi (Chief Queens) of first three Mauryan Emperors
Chandragupta Maurya -
1- Ragyi Durdhara (Belonged to Mauryan lineage and according to Mahavansh Tika daughter of Chandragupta's eldest maternal uncle, possibly adopted to make her suitable for Agramahishi as she was a commoner).
2- Bhavishya Purana says daughter of a Yavana king Suluva who ruled over Paursa was his next Agramahishi (possibly he was a normal Satrap of one of the north western satrapies)
Bindusara-
1- Janpad Kalyani Subhadhrangi or Dharma (Only in one source, maybe for a brief time and then lost favour)
2- Mother of Sushima (her name and origins are not known)
Ashoka
1- Vedisha Devi or Mahadevi willingly didn't accept being Agramahishi but she had title of Mahadevi to give honour to her sacrifices and support for Ashok when he was just a prince and gave him two illustrious and well learned children.
2- Agramahishi Asandhimitra - She was barren so she adopted Charumati, daughter of Ashok born from a concubine. Charumati was Ashok's favourite daughter and she cared for Ashok in her last days.
3- Agramahishi Tisyarakshita - An evil hearted lady who charmed Ashoka with her looks and dance. She saved Ashok from a disease so he made her Agramahishi. Some scholars calls Karuwaki and Tisyarakshita as same woman as both are called Dwitiya Devi. She blinded Kunala, Ashok's favourite son and crown prince.
. I bet they doesn't even know about Asandhimitra being the most important or chief consort of Samrat Ashoka. But I don't regret that cause if they knew, they would have made her an in and out vamp just like rukaiya begum in JA which she was not
Thats why I would never like to see the fictional portrayal of her as an evil queen for the sake of entertainment. Wish someday her characters will be presented on screen giving the required respect she deserve 
.... full of inaccuracy.. Just they took the name and ideas from previous screen version, never even bothered to research a little to know the truth...
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