Although for the purpose of this articleEnglish literature is treated as being confined to writings inEnglish by natives or inhabitants of theBritish Isles, it is to a certain extent the case that literature-and this is particularly true of the literature written inEnglish--knows no frontiers. Thus,English literature can be regarded as a cultural whole of which the mainstream literatures of the Unit- ed States,Australia, New Zealand, andCanada and important elements in the literatures of other commonwealth countries are parts. It can be argued that no singleEnglish novel attains the universality of the Russian writer Leo Tolstoy’s War and Peace. Yet in the MiddleAges the OldEnglish literature was influenced and gradually changed by the Latin and French writings, eminently foreign in origin, in which the churchmen and the Norman (诺曼) conquerors expressed themselves. From this combination emerged a flexible and subtle linguistic instrument exploited by GeoffreyChaucer (乔叟) and brought to supreme application by William Shakespeare.