This rare and interesting name is of medieval Welsh origin and derives from the personal name "Goronwy", the Old Welsh "Guorgouue", of unknown etymology. However, this name has numerous variants, for example, Gronwy, Gronow(e), Gronou, Gron(n)o, Gronewey, Grannos and Gronous. The practice of the medieval Anglo-Norman scribe was often to change the "gw" to "w", thus resulting in further variant spellings, for example "David ap Wronu". This name was first recorded as a surname in the late 14th Century (see below) and is recorded in the variant spellings of Grannos and Gronous in the border Counties of Shropshire and Herefordshire, the earliest being the marriage of Elizabeth Grannos and Richard Beavon, on October 2nd 1662, at Fitz. Salop, with a later recording of the marriage of James Gronous and Dorcas Hergest in 1669 at Kington, Herefordshire. One Thomas Gronous was a High Sheriff of London in 1783. The first recorded spelling of the family name is shown to be that of Kenwrig ap Grono, which was dated 1391, in the "Extent of Chirkland 1391 - 1392", G.P. Jones, during the reign of King Richard 11, known as "Richard of Bordeaux", 1377 - 1399. 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.