Editing Natural border (section)

{{Short description|State boundaries which follow geographic features such as rivers, mountains, etc.}}
{{Redirect|Natural boundaries|other boundaries|Boundary (disambiguation){{!}}Boundary}}
[[Image:2009-08-01-ffto-slubice-by-RalfR-15.jpg|thumb|[[Oder|The Oder]], a natural border between [[Poland]] and [[Germany]]]]
A '''natural border''' is a [[border]] between [[Sovereign state|states]] or their subdivisions which is concomitant with natural formations such as [[river]]s or [[mountain range]]s. The "doctrine of natural boundaries" developed in Western culture in the 18th century being based upon the "natural" ideas of [[Jean-Jacques Rousseau]] and developing concepts of [[nationalism]].<ref>{{Cite book|author=Dikshit, Ramesh Dutta|year=1999|title=Political Geography: the Spatiality of Politics|edition=3rd|publisher=McGraw-Hill|location=New Delhi|page=70|isbn=978-0-07-463578-0}}</ref> The similar concept in China developed earlier from natural zones of control.<ref>See {{Cite book|author=Wheatley, Paul|authorlink = Paul Wheatley (geographer)|year=1971|title=The Pivot of the Four Quarters: a preliminary enquiry into the origins and character of the ancient Chinese city |location=Chicago|publisher=Aldine Publishing|pages= 170&ndash;173|isbn=978-0-85224-174-5}}</ref>

[[File:EE natural borders.jpg|thumb|[[Eastern Europe|Eastern European natural borders]]]]
[[File:Map of the Grand Duchy of Lithuania (pink) and the Crown of the Kingdom of Poland (red) in 1386 - 1434.png|thumb|[[Grand Duchy of Lithuania|Grand Duchy of Lithuania, Ruthenia and Samogithia in 1386–1434]]]]

Natural borders have historically been [[strategically]] useful because they are easily [[defense (military)|defended]]. Natural borders remain meaningful in modern warfare even though [[military technology]] and [[military engineering|engineering]] 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]], and later, the [[Roman Empire]] expanded continuously until it reached certain natural borders: first the [[Alps]], later the [[Rhine]] river, the [[Danube]] river and the [[Sahara]] desert. From the [[Middle Ages]] onwards until the 19th century, [[France]] sought to expand its borders towards the Alps, the [[Pyrenees]], and the Rhine River.<ref>{{Cite book|author=Carlton, J. H. Hayes|year=1916|title=A Political and Social History of Modern Europe, volume 1|publisher= Macmillan|location=New York|page=119|oclc=2435786}}</ref>

Natural borders can be a source of territorial disputes when they shift. One such example is the [[Rio Grande]], which defines part of the border between the [[United States]] and [[Mexico]], whose movement has led to [[Rio Grande border disputes|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]]-designated political boundaries, goes against nature by modifying the borderland's natural geography. For one, China's [[Song dynasty|Song Dynasty]] built an extensive defensive forest in its northern border to thwart the nomadic [[Khitan people]].<ref>{{Cite journal|last=Chen|first=Yuan Julian|date=July 2018|title=FRONTIER, FORTIFICATION, AND FORESTATION: DEFENSIVE WOODLAND ON THE SONG–LIAO BORDER IN THE LONG ELEVENTH CENTURY|journal=Journal of Chinese History|language=en|volume=2|issue=2|pages=313–334|doi=10.1017/jch.2018.7|issn=2059-1632|doi-access=free}}</ref>