Anglo-Norman language general use of the word "acre" for land measurement in Normandy until metrication in the 19th century, but these words are probably linguistic traces of Saxon or Anglo-Scandinavian settlements between the 4th and the 10th centuries in Normandy. Otherwise the direct influence of English in mainland Norman (such as "smogler" - to smuggle) is from direct contact in later centuries with English, rather than Anglo-Norman. When the Normans invaded England, Anglo-Saxon literature had reached a very high level of development. The important Benedictine monasteries both wrote chronicles and guarded other works in Old English. However, with the arrival of the
Germanic peoples classical source, modern linguists sometimes designate the Frankish language (and its descendant Dutch) as Istvaeonic, although the geographical term "Weser-Rhine Germanic" is often preferred. However, the classical ""Germani"" near the Rhine, to whom the term was originally applied by Caesar, may not have even spoken Germanic languages, let alone a language recognizably ancestral to modern Dutch. The close relatives of Dutch, Low German, Anglo-Saxon and Frisian, are in fact sometimes designated as Ingvaeonic, or alternatively, "North-Sea Germanic". Frankish, (and later Dutch, Luxembourgish and the Frankish dialects of German in Germany) has continuously been intelligible to some extent with both "Ingvaeonic"