English is a West Germanic language that was originally used in medieval England and has become the most widely spoken language in the world due to its vast colonial territories. The ancestors of the English people, the Anglo-Saxon tribes, were one of the Germanic tribes that later migrated to the British Isles and became known as England. Both names originated from the Anglia region on the Baltic Peninsula. This language is closely related to Frisian and Low Saxon, and its vocabulary has been influenced by other Germanic languages, especially the North Germanic languages, and has been extensively written in Latin and French. English has been evolving for over 1400 years. The earliest form of English was a group of West Germanic dialects (Ingvaeonic) brought to Britain by Anglo-Saxon immigrants in the 5th century, collectively known as Old English. Middle English began in the late 11th century with the Norman conquest of England; in 1476, William Caxton introduced the printing press to England and began publishing the first printed book in London, expanding the influence of English. Since the 17th century, Modern English has spread around the world under the extensive influence of Britain and the United States. Through various types of print and electronic media in these countries, English has become one of the dominant international languages and also holds a dominant position in many regions and professional environments, such as science, navigation, and law.