https://biography.wales/article/s-RICE-NEW-1500
RICE family, of Newton and Dynevor, Carmarthenshire
Descended from Gruffudd ap Nicolas, the family, later known as the Rices, reached their highest point of wealth and influence in the person of Sir Rhys ap Thomas. His grandson, Sir RHYS AP GRUFFYDD, who married, in 1524, lady Catherine Howard, daughter of the 2nd duke of Norfolk, was executed for treason in 1531. The evidence for his guilt was slight and his real offence was probably his Catholicism and his opposition to Anne Boleyn.
Griffith Rice's son, WALTER RICE (c. 1560 - 1611), was Member of Parliament for Carmarthenshire
Lewys Dwnn, whose pedigree of the family was signed by Walter Rice, described him as ‘one of James I pensioners.’ He was knighted in 1603.
In the next generation, HENRY RICE (c. 1590 - c. 1651), continued the effort to recover lost ground. In 1625 and 1629 he petitioned Charles I for a grant of such of his greatgrandfather's estates as remained in the hands of the Crown, claiming that Mary and Elizabeth had promised as much to his father and grandfather. He was certainly the anonymous author of the ‘Life of Rhys ap Thomas’ and the defence of Rhys ap Gruffydd, published in the Cambrian Register, vols. i and ii (1793 and 1796), and they were part of his campaign for the recovery of the family estate. There is no evidence that either he or his son, EDWARD RICE, played any part in the Civil Wars; both held lands in Dynevor and Newton in 1651, and the latter was high sheriff of Carmarthenshire in 1663. The date of his death is uncertain and his estates passed to his brother, WALTER RICE, who was nominated deputy-lieutenant of Brecknock in 1674.
The date of his death is uncertain and his estates passed to his brother, WALTER RICE, who was nominated deputy-lieutenant of Brecknock in 1674.
Also, info on the Vaughn family and their connections to the Rices:
https://biography.wales/article/s-VAUG-GEL-1500
And, Rice family, barons Dynevor:
https://archives.library.wales/index.php/rice-family-barons-dynevor
Hope that helps.