Yale (surname)
The surname Yale is derived from the Welsh word "iâl", meaning "fertile ground". Iâl was the name of an important commote in Denbighshire, whose rulers, the princes of Powys Fadog, lords of Yale, were a cadet line of the royal House of Powys. For hundreds of years, their ancestral seat was at Castle Dinas Bran in Yale. Afterwards, baron Ellis ap Griffith attached the name to the estate of Plas-yn-Iâl, from which the House of Yale (or Yale family) became known.
The Yale surname was thus adopted from the maternal side of the family, while their coat of arms, which inspired those of Yale College, came from the paternal side, through the Fitzgeralds of Corsygedol. In the early modern period, the family produced Elihu Yale, a governor of Madras and benefactor of Yale University, ensuring that the name "Yale" achieved lasting prominence well beyond Wales.