Ashwapati

Ashwapati or Aśwapati (अश्‍वपति) is the appellation of many kings in Hindu mythology. It means 'Lord of horses.' It was an appellation comparable to that of the knight or Ritter in Europe. According to Ramayana Ashwapati was king of Kekeya Kingdom the land of fine horses. He was father of a daughter Kaikeyi (Favorite queen of King Dasharatha) and seven sons. one of the important son was Yudhajeet, who played important role in great epic Ramayana.Ashwapati was Maternal Grand father of Bharata.

Due to a boon, Ashwapati was able to understand the language of the birds. However, this was accompanied by a caveat that if he ever revealed the content of bird speak to anyone, even his own mother, that he would forthwith lose his life. One day, the King and his Queen were strolling through the palace gardens when Ashwapati happened to overhear the conversation of a pair of mated swans. The conversation so amused him that he laughed heartily, instigating his wife's curiosity. Despite being aware of the fact that Ashwapati could not divulge the content of the conversation to her without losing his life, Kaikeyi's mother insisted on knowing the cause of the King's mirth. When Ashwapati realized that his wife cared little for his life or well-being, he had her banished to her parents' home.

Dasharatha made promise to Ashwapati and Yudhajeet at the time of Kaikeyi marriage that the son born of her womb would succeed him as King of Kosala. and by crowning Rama as king Dasharatha is doing injustice to whole Kekeya Kingdom.

...
Wikipedia