Sociological triggers for language change refer to such radical socio-political changes as wars, invasions, occupation, colonialization, and language planning and standardization policies. A typical example in the history of English is the Norman Conquest, a military event that marked the dawning of the Middle English period. This means that Middle English began with the arrival of the Norman French invaders in English under William,the Conqueror in 1066. And for about a century and a half after the Norman Conquest, French remained as the language of the ruling class,as far as literature and administration were concerned. So Middle English was deeply influenced by Norman French in vocabulary and grammar. For example, such terms as army , court , defense , faith , prison and tax, came from the language of the French rulers.