Wales Beaumaris, Caernarfon and Conwy. His son, the future Edward II, was born at Edward's new castle at Caernarfon in 1284. He became the first English Prince of Wales in 1301, which at the time provided an income from northwest Wales known as the Principality of Wales. The title is granted by the monarch to the heir apparent as a personal honour or dignity, and is not heritable, merging with the Crown on accession to the throne. After the failed revolt in 1294–95 of Madog ap Llywelyn – who styled himself Prince of Wales in the Penmachno Document – and the
Princess of Wales Wales, but this was incorrect because she was not a princess in her own right. Although not granted the title in her own right, the future Queen Mary I was, during her youth, invested by her father, King Henry VIII, with many of the rights and properties traditionally given to the Prince of Wales, including use of the official seal of Wales for correspondence. For most of her childhood, Mary was her father's only legitimate heir, and for this reason she was often referred to as "the Princess of Wales", although Henry never formally created her as such. For example,