I am a Japanese history enthusiast. Recently, I was watching a documentary explaining that the early Habsburg domains were located near the Rhine–Danube watershed, a strategic area for trade and transport. That led me to learn about the completion of the Main–Danube Canal in 1992, which required significant engineering to overcome elevation differences and also long-term political cooperation among European states.
While reading about this, I realized that China had already constructed large-scale canal systems lixing major river basins more than a millennium earlier (for example, the Sui–Tang Grand Canal in the 7th century). This made me wonder whether there is a deeper structural difference behind these developments.
 
我是一名日本历史爱好者。最近,我正在看一部纪录片,其中解释了哈布斯堡家族早期的领地位于莱茵河—多瑙河分水岭附近,那是贸易和交通的战略要地。这促使我了解了 1992 年完工的美因河—多瑙河运河,该工程需要高超的工程技术来克服海拔差异,同时也需要欧洲各国之间长期的政治合作。
 
在阅读相关资料时,我意识到中国早在 1000 多年前就已经建造了连接主要河流流域的大规模运河系统(例如 7 世纪的隋唐大运河)。这让我不禁思考,在这些发展背后是否存在更深层次的结构性差异。
 
Why did large-scale political reunification repeatedly occur in China — for example after the Warring States period (Qin–Han), after the Three Kingdoms and Northern–Southern dynasties, and again with the Sui–Tang reunification — whereas post-Roman Europe did not re-establish comparable long-term political unity? Instead, Europe developed a system of multiple competing states and balance-of-power politics.
Some possible explanatory factors I have encountered include:
 
为什么中国一再出现大规模的政治统一——例如战国时代之后的秦汉统一、三国和南北朝之后的隋唐统一——而罗马帝国之后的欧洲却未能重新建立起类似的长期政治统一?相反,欧洲发展出了一种多国竞争和权力制衡的政治体系。
 
Some possible explanatory factors I have encountered include:
The geography of the North China plain compared to Europe’s mountains, peninsulas, and divided river systems
Persistent steppe military pressure on northern China
Bureaucratic continuity in China, including standardized written administration
The evolution of vernacular languages and decentralized feudal structures in Europe
 
我所接触到的一些可能的解释因素包括:
华北平原的地理环境:与欧洲多山、多半岛且河流系统破碎的地理特征进行对比。
持续的草原军事压力:对中国北方构成的外部威胁。
中国的官僚连续性:包括标准化的书面行政体系。
欧洲方言的演变与去中心化的封建结构。
 
Europe also shared a common Christian religious culture and Latin intellectual tradition. Why did this not produce comparable political reunification?
I am not asking which society is superior. I am trying to understand why these two different political trajectories emerged, and whether historians identify key turning points where the outcome might have been different.
 
欧洲同样拥有共同的基督教宗教文化和拉丁语知识传统。为什么这没有产生类似的政治统一?
我并不是在问哪种社会更优越。我试图理解为什么会出现这两种不同的政治发展轨迹,以及历史学家是否确定了某些可能导致不同结果的关键转折点。