Periodization is the attempt to categorize or divide historical time into discrete named blocks.
Periodization is a complex problem in history. History is in fact continuous, and so all systems of periodization are to some extent arbitrary. It is nevertheless necessary to divide up history in order to make sense of the past and to articulate changes over time. Furthermore different nations and cultures experience different histories, and so will require different models of periodization. Periodizing labels are being challenged and redefined all the time. Thus an historian may claim that 'there was no such thing as the Renaissance', while others will defend the concept.
The reasons for this are complex. Periodizing blocks will inevitably overlap, or even seemingly contradict one another. Furthermore, certain periodizing concepts only apply in specific conditions. Some have a cultural usage (such the ' Romantic period'), others refer to historical events ('the Inter War years: 1918-1939'), yet others are defined by decimal numbering systems ('the 1960s', 'The Seventeenth Century'). Others are named from influential or talismanic individuals (the Victorian period, the Elizabethan period, the Napoleonic Era).
Some of these usages will also be geographically specific. This is especially true of periodising labels derived from individuals or ruling elites: such as the Jacksonian era in America, or the Meiji era in Japan, or the Merovingian period in France. Cultural terms may also have a limited reach. Thus the concept of the 'Romantic Period' maybe meaningless outside of Europe and of Europe-influenced cultures. Likewise, the '1960s', though technically applicable to anywhere in the world according to Common Era numbering, only has the specific cultural connotations that it does in some countries. For this reason it may be possible to say such things as 'the 1960s never occurred in Spain'. This would mean that the sexual revolution, counter-culture, youth rebellion and so on never developed during that decade in a conservative Roman Catholic culture and under Franco's fascist regime. Likewise it is possible to claim, as the historian Arthur Marwick has, that the '1960s' began in the late 1950s and ended in the early 1970s. His reason for saying this is that the cultural and economic conditions that define the meaning of the period covers more than the accidental fact of a 10 year block beginning with the number 6. This extended usage is termed the 'long 1960s'. This usage derives from other historians who have adopted labels such as the 'Long Eighteenth Century' to reconcile arbitrary decimal chronology with meaningful cultural and social phases. Eric Hobsbawm has also argued for what he calls the 'Short Twentieth Century' - encompassing the period from the First World War through to the end of the Cold War.
Similar problems attend other labels. Is it possible to use the term 'Victorian' outside of Britain? It sometimes is used if it is thought that its connotations usefully describe the politics, culture and economic conditions characteristic of the last two-thirds of the nineteenth century. Nevertheless periodizing terms often have negative or positive connotations which may affect their usage. This would include 'Victorian', which is often used negatively to suggest sexual repression, class conflict, heavy industry and so on. Other labels such as 'Renaissance' have strongly positive characteristics. As a result, these terms will sometimes be extended in meaning. Thus the 'English Renaissance' is virtually identical in meaning to the 'Elizabethan period'. However the Carolingian Renaissance is said to have occurred during the reign of the Frankish king Charlemagne. There is a space of approximately seven hundred years between these two 'Renaissances'.
Because of these various positive and negative connotations, some periods are luckier than others regarding their names, but this can lead to problems such as the ones outlined above. The word Renaissance, meaning 'rebirth', though in English commonly known by its French name, was created by an Italian poet still perceived as belonging to the beginnings of the period, Petrarch. Its dominant usage still refers to the cultural changes that occurred in Italy, and which culminated in what is termed the High Renaissance, at around 1500. This concept applies dominantly to the visual arts, referring to the work of Michelangelo, Raphael and Leonardo da Vinci. Secondarily it is applied to other arts, but it is disputed whether it is useful to describe a phase in economic, social and political history. Most professional historians (defined as paying members of organizations devoted to the propagation of history in higher education, like the American Historical Association) now refer to the historical 'period' commonly known as The Renaissance as the Early Modern period. There has been no substantive change in the courses taught or books published to correspond to the change in period nomenclature. But this in part reflects differences between social history and cultural history.
The term Middle Ages also derives from Petrarch. He was comparing his own period to the Ancient or Classical world, seeing his time as a time of rebirth after a dark intermediate period, the Middle Ages. The idea that the Middle Ages was a 'middle' phase between two other large scale periodizing concepts - Ancient and Modern - still persists. Smaller periodizing concepts such as Dark Ages occur within it. Both 'Dark Ages' and 'Middle Ages' still have negative connotations - the latter especially in its Latin form 'Medieval'. However other terms, such as Gothic architecture, used to refer to a style typical of the High Middle Ages have largely lost the negative connotations they initially had, only to acquire others (see Gothic)
The Gothic and the Baroque were both named during subsequent stylistic periods when the preceding style was unpopular. The word "Gothic" was applied as a pejorative term to all things Northern European and, hence, barbarian, by Italian writers during the 15th and 16th centuries. The word "baroque" (probably) was used first in late 18th century French about the irregular natural pearl shape and later about an architectural style perceived to be "irregular" in comparison to the highly regular Neoclassical architecture of that time. Subsequently these terms have become purely descriptive, and have largely lost negative connotations. However the term 'Baroque' as applied to art (for example Rubens) refers to a much earlier historical period than when applied to music (Handel, Bach). This reflects the difference between stylistic histories internal to an art form and the external chronological history beyond it.
In many cases people living through a period are unable to identify themselves as belonging to the 'period' that historians may later assign to them. This is partly because they are unable to predict the future, and so will not be able to tell whether they are at the beginning, middle or end of a period. Another reason may be that their own sense of historical development may be determined by religions or ideologies that differ from those used by later historians.
It is important to recognise the difference between self-defined historical periods, and those which are later defined by historians. At the beginning of the 20th Century there was a general belief that culture, politics and history were entering a new era - that the new century would also be a new 'era' in human experience. This belief was repeated at the beginning of the 21st Century, though in a very different way. Other cultural and historical phases have only been described many years, or even centuries, later.