Was it William ap Thomas or William Herbert that had the sudden rise to wealth?
William Herbert was the son of William Ap Thomas, William Ap Thomas, came from minor gentry to be the lord of Raglan Castle, he married two rich heiresses and died a rich and powerful man. His son inherited his welath and castles, was later made earl of pembroke established the ‘Herbert’ (he anglicised his name) family – a powerful dynasty. I would say it was Ap Thomas who had the sudden rise to wealth, while William Herbert who inherited did achieve greater power than his father, through his closeness to the Yorkist king, the drama of his rise was less compared to his father.