The fall of Constantinople was the Ottoman Empire's invasion of Constantinople, capital of the Eastern Roman Empire, also known as the Byzantine Empire. This historical event occurred on May 29, 1453 and signified the end of the Middle Ages and the beginning of the Modern Age. The beginnings of this event date from the time of the Christian crusades, when in 1204, during the fourth crusade, they took the city by storm and annexed it to the Latin empire.

The localization of industry refers to the concentration of many firms of an industry (i.e. firms producing similar goods or services) in an area e.g. concentration of many leather craft industries in London.