This unusual and interesting name is Welsh, from the personal name "Ble(i)ddyn", which was originally a byname (nickname) meaning "wolf cub". The derivation is from "blaida", wolf, plus the diminutive suffix "yn". Heroes of medieval Wales were often referred to as "Blaidd", although the term was also sometimes used to describe a cruel man, or one who pretended friendship while remaining an enemy. One Meredith ap Blethyn was prince of North Wales in the 11th Century. "Ap" is the Welsh patronymic form, meaning "son of" and it is this form that produced the modern variants Plevin, Pleavin, Pleven and Pleaden, The "p" of "ap" being absorbed into the name. The "records of Wills at Chester" (1681 1700) shows one William Pelvin of Kinnerton in 1685. The first recorded spelling of the family name is shown to be that of Robert Blevyn. which was dated 1273, in the "Hundred Rolls, Norfolk". during the reign of King Edward 1, known as "The Hammer of the Scots", 1272 - 1307. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.