The German surname of ARNDTS is of the baptismal group of surnames meaning 'the son of Arnold'. The name was derived from the Germanic elements meaning 'EAGLE' and 'RULE'. Its popularity in the Middle Ages is shown by its frequent use as a surname. The name is also spelt ARNE, ARNHOLD, ARNOLL, ARNOLD, ARNAUDIN and ARNISON to name but a few. ARNOLD of Brescia (1100-1155) was the Italian Augustinian monk, who attacked the holding of property by the Catholic church; he was hanged and burnt, and his ashes were thrown into the Tiber. Thomas Arnold (1795-1842) was the Headmaster of Rugby, which he raised to the rank of a great public school. Matthew Arnold (1822-1888) was an English poet and critic of distinction, and the son of Thomas.It was not until the 10th century that modern hereditary surnames first developed, and the use of fixed names spread, first to France, and then England, then to Germany and all of Europe. In these parts of Europe, the individual man was becoming more important, commerce was increasing and the exact identification of each man was becoming a necessity. Even today however, the Church does not recognise surnames. Baptisms and marriages are performed through use of the Christian name alone. Thus hereditary names as we know them today developed gradually during the 11th to the 15th century in the various European countries. Because of the close relationship between the English and German languages, some Germans are able to transform their names to the English form just by dropping a single letter. Many Germans have re-spelt their names in America. A great number of immigrants from Germany settled in Pennsylvania. After the start of the first World War, Germans in great numbers Anglicized their names in an effort to remove all doubt as to their patriotism. Afterwards some changed back, and then during World War II the problem became acute once more, and the changing started all over again, although not with as much intensity. German or Teutonic heraldry extended its sphere of influence over central Europe and spread into Scandinavia. It is most notable for its design and treatment of crests, most of which reflect the arms in the charge or tinctures (colours) or both, which is unknown in British heraldry. Teutonic Europe assembled many arms on a single shield, each bearing its corresponding crest on a helmet.