A natural border is a

border Borders are usually defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political borders ca ...

between states or their subdivisions which is concomitant with natural formations such as

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of ...

s or

mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have ari ...

s. The "doctrine of natural boundaries" developed in Western culture in the 18th century being based upon the "natural" ideas of

Jean-Jacques Rousseau Jean-Jacques Rousseau (, ; 28 June 1712 – 2 July 1778) was a Genevan philosopher, writer, and composer. His political philosophy influenced the progress of the Age of Enlightenment throughout Europe, as well as aspects of the French Revolu ...

and developing concepts of

nationalism Nationalism is an idea and movement that holds that the nation should be congruent with the State (polity), state. As a movement, nationalism tends to promote the interests of a particular nation (as in a in-group and out-group, group of peo ...

. The similar concept in China developed earlier from natural zones of control. EE natural borders

Natural borders have historically been

strategically Strategy (from Greek στρατηγία ''stratēgia'', "art of troop leader; office of general, command, generalship") is a general plan to achieve one or more long-term or overall goals under conditions of uncertainty. In the sense of the "art ...

useful because they are easily defended. Natural borders remain meaningful in modern warfare even though

military technology Military technology is the application of technology for use in warfare. It comprises the kinds of technology that are distinctly military in nature and not civilian in application, usually because they lack useful or legal civilian application ...

and

engineering Engineering is the use of scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad range of more speciali ...

have somewhat reduced their strategic value. Expanding until natural borders are reached, and maintaining those borders once conquered, have been a major policy goal for a number of states. For example, the

Roman Republic The Roman Republic ( la, Res publica Romana ) was a form of government of Rome and the era of the classical Roman civilization when it was run through public representation of the Roman people. Beginning with the overthrow of the Roman Ki ...

, and later, the

Roman Empire The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post-Roman Republic, Republican period of ancient Rome. As a polity, it included large territorial holdings aro ...

expanded continuously until it reached certain natural borders: first the

Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...

, later the

Rhine ), Surselva, Graubünden, Switzerland , source1_coordinates= , source1_elevation = , source2 = Rein Posteriur/Hinterrhein , source2_location = Paradies Glacier, Graubünden, Switzerland , source2_coordinates= , source ...

river, the

Danube The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , pa ...

river and the

Sahara , photo = Sahara real color.jpg , photo_caption = The Sahara taken by Apollo 17 astronauts, 1972 , map = , map_image = , location = , country = , country1 = , ...

desert. From the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

onwards until the 19th century,

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

sought to expand its borders towards the Alps, the

Pyrenees The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to ...

, and the Rhine River. Natural borders can be a source of territorial disputes when they shift. One such example is the

Rio Grande The Rio Grande ( and ), known in Mexico as the Río Bravo del Norte or simply the Río Bravo, is one of the principal rivers (along with the Colorado River) in the southwestern United States and in northern Mexico. The length of the Rio G ...

, which defines part of the border between the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

and

Mexico Mexico (Spanish language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

, whose movement has led to multiple conflicts. Natural borders are not to be confused with landscape borders, which are also geographical features that demarcate political boundaries. Although landscape borders, like natural borders, also take forms of forests, water bodies, and mountains, they are manmade instead of natural. Installing a landscape border, usually motivated by demarcating

treaty A treaty is a formal, legally binding written agreement between actors in international law. It is usually made by and between sovereign states, but can include international organizations, individuals, business entities, and other legal per ...

-designated political boundaries, goes against nature by modifying the borderland's natural geography. For one, China's

Song Dynasty The Song dynasty (; ; 960–1279) was an imperial dynasty of China that began in 960 and lasted until 1279. The dynasty was founded by Emperor Taizu of Song following his usurpation of the throne of the Later Zhou. The Song conquered the res ...

built an extensive defensive forest in its northern border to thwart the nomadic

Khitan people The Khitan people (Khitan small script: ; ) were a historical nomadic people from Northeast Asia who, from the 4th century, inhabited an area corresponding to parts of modern Mongolia, Northeast China and the Russian Far East. As a people desc ...

Criticism

In Chapter IV of his 1916

book A book is a medium for recording information in the form of writing or images, typically composed of many pages (made of papyrus, parchment, vellum, or paper) bound together and protected by a cover. The technical term for this physical ...

''The New Europe: Essays in Reconstruction'', British

historian A historian is a person who studies and writes about the past and is regarded as an authority on it. Historians are concerned with the continuous, methodical narrative and research of past events as relating to the human race; as well as the st ...

Arnold J. Toynbee Arnold Joseph Toynbee (; 14 April 1889 – 22 October 1975) was an English historian, a philosopher of history, an author of numerous books and a research professor of international history at the London School of Economics and King's Colleg ...

criticized the concept of natural borders.{{Cite book, url=https://www.google.com/books/edition/The_New_Europe/AIHTAAAAMAAJ?hl=en&gbpv=1&dq=The+New+Europe:+Some+Essays+in+Reconstruction&pg=PA9&printsec=frontcover, title=The New Europe: Some Essays in Reconstruction, year=1916 Specifically, Toynbee criticized this concept as providing a justification for launching additional wars so that countries can attain their natural borders. Toynbee also pointed out how once a country attained one set of natural borders, it could subsequently aim to attain another, further set of natural borders; for instance, the

German Empire The German Empire (),Herbert Tuttle wrote in September 1881 that the term "Reich" does not literally connote an empire as has been commonly assumed by English-speaking people. The term literally denotes an empire – particularly a hereditary ...

set its western natural border at the

Vosges Mountains The Vosges ( , ; german: Vogesen ; Franconian and gsw, Vogese) are a range of low mountains in Eastern France, near its border with Germany. Together with the Palatine Forest to the north on the German side of the border, they form a singl ...

in 1871 but during

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

, some Germans began to advocate for even more western natural borders—specifically ones that extend all of the way up to

Calais Calais ( , , traditionally , ) is a port city in the Pas-de-Calais department, of which it is a subprefecture. Although Calais is by far the largest city in Pas-de-Calais, the department's prefecture is its third-largest city of Arras. Th ...

and the

English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" ( Cotentinais) or ( Jèrriais), ( Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Ka ...

—conveniently justifying the permanent German retention of those Belgian and French territories that Germany had just conquered during World War I. As an alternative to the idea of natural borders, Toynbee proposes making free trade, partnership, and cooperation between various countries with interconnected economies considerably easier so that there would be less need for countries to expand even further—whether to their natural borders or otherwise. In addition, Toynbee advocated making national borders based more on the principle of national self-determination—as in, based on which country the people in a particular area or territory actually wanted to live in.

References

Borders *Main

Criticism

See also

References