 The arms of Maud Green , Lady Parr , mother of Catherine Parr ( the last of the six wives of Henry VIII and stepmother to Elizabeth I ) , were of three stags on an azure background , and this became one of the elements of the arms of Catherine Parr on her marriage . Her sister , Anne Parr , married William , 1st Earl of Pembroke , whose grandson ( the 3rd Earl , also called William ) became the first Visitor of the college in 1622 . Maud Green 's arms are depicted in plasterwork from about 1592 at Powis Castle , owned by a kinsman of the earls . One writer has suggested that the college may have adopted the arms in order to be associated with one of the leading Welsh families of the day . 
