The German language has the most native speakers of any language in the European Union. It is spoken principally in Germany, Austria, Liechtenstein, and large sections of Switzerland and Luxembourg. Several former colonies of these nations, such as Namibia, have a notable number of German-speaking residents as well as some Latin American countries, like Brazil and Argentina, due to the large influx of German immigrants that took place over a century ago. German was the official language of the Hapsburg Empire, which ruled a sizable portion of Central and Eastern Europe. In 1860, rules of grammar and orthography of German made their first appearance in the Duden Handbook. Official revisions of the rules were not made until the Rechtschreibreform (a significant reform of German spelling), which was officially enacted by governmental representatives from all of the German-speaking nations around the world in 1996. German is today spoken by an estimated 130 million people.