This unusual and interesting surname is of Anglo-Saxon origin, and has two possible sources. Firstly, it may be from a topographical name for someone who lived on a hillock, derived from the Olde English pre 7th Century "cnyll", hillock, a byform of "cnoll", meaning "top of a hill". Topographical surnames were among the earliest created, since both natural and man-made features in the landscape provided easily recognisable distinguishing names. The second source is locational from a place called Knill, in Herefordshire, derived from the Olde English "cnyll", as before. The placename was first recorded as "Chenille" in the Domesday Book of 1086, and it was variously recorded as "Cnulla" and "Knulle" in the Book of Fees of 1242 and 1249, respectively. Locational surnames were developed when former inhabitants of a place moved to another area, usually to seek work, and were best identified by the name of their birthplace. Among the five namebearers listed in the "Dictionary of National Biography" is one William Adolphus Knell (deceased 1875), a marine-painter who exhibited at the Royal Academy and the British Institution (1826 - 1866); his painting the "Landing of Prince Albert" was purchased for the royal collection. The first recorded spelling of the family name is shown to be that of Alvredus de Knelle, which was dated 1220, in the "Curia Regis Rolls of Sussex", during the reign of King Henry 111, known as "The Frenchman", 1216 - 1272. 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.