Language is not only the most important tool of communication, but, at the same time, it forms the base for aesthetics, philosophy, cognition and offers the possibility to identify the members of the own group. It also acquires an important function in politics. Especially, in multilingual societies ethnolinguistical conflicts are generated mostly by their different position in language hierarchy. Sometimes, one language dominates all the others in public affairs and becomes even a global language as English in our days. In the EU e.g. this language dominates the others, despite the facts that it is not the mother tongue of the major part of the community and all member languages have de jure the same rights. The role of English is not as unique as sometimes claimed. A similar position had Latin already in the past or Russian, Polish and French in modern times. In the last years the situation for Russian changed completely when it lost its dominant position in many countries. In the case of the Baltic States the previous dominant language became even the dominated one of a minority which lost all its former privileges. Similar was the fate of French or Polish losing their predominant position of the past. The example of Russian in the Baltic States offers to sociolinguistics an interesting field of research and will enable us to formulate some general rules connected with the fundamental changes from a dominant to a dominated language. Certainly, also the position of English will not remain untouched in future and the function of a global language is always a transitory one.