Back in days of Roman Empire, three main European barbarians in their eyes were Germans, Celts and Slavs, and they were objects of conquest and attacks. The blond hair and blue eyes at that time were not upper-class people who were high above, but lower-class people who were in a pitiful position.
After Western Expedition of Mongol Empire, Russia, which was mainly built by Russ and Slavs, began to gradually rise, but after Ottomans destroyed Eastern Roman Empire, Russia called itself "Third Roman Empire"!
Why did a Slav who was once attacked and despised by Roman Empire, after his rise, suddenly called himself "Third Rome", and Britain, France, Germany and Italy did not refute this?
For Chinese, Qin, Han, Tang and Song dynasties had their own greatness. The "Roman Empire" is at best equivalent to a dynasty in Chinese history, but it only lasted for a long period of time, and there is no complex that is hard to let go. But for Westerners after Rome there is no Rome... The name "Rome" is extremely important and has a very special meaning.
On eve of fall of Western Han Dynasty, Roman Empire was formally established. During Eastern Han Dynasty, territory of Roman Empire reached its peak. She controlled about 5 million square kilometers of land and ruled most of Western Europe, largest monarchical empire in ancient European history. Therefore, Roman Empire founded by Octavian was called "First Roman Empire".
In 395 A.D. e. Roman emperor Theodosius I divided empire between his two sons and divided east and west. Since then, Roman Empire has never been unified. Among them, capital of Western Roman Empire was at Milan, Italy, which lasted less than a hundred years before being destroyed by rebellion of Roman mercenary leader Odoacer; Eastern Roman Empire, also known as "Byzantine Empire". ", with its capital in Constantinople, which is now Istanbul in Turkey, was destroyed by Ottoman Empire after more than 1000 years of service, also known as "Second Roman Empire".
There is another saying about "Second Roman Empire", which is "Holy Roman Empire", that is, Roman Empire, founded by German Otto I in Middle Ages, and later elevated to "Holy Roman Empire". ", based on Germanic region As a core, including entire territory of Austria, Netherlands, Belgium, Switzerland, etc., as well as parts of France, Italy, etc., represents a very large empire in European history.
The Holy Roman Empire was First German Reich, Germany from Franco-Prussian War until end of World War I was Second German Reich, and later Hitler hoped to create a Third German Reich.
Many historical and cultural things that Chinese consider normal are actually very valuable in West. From time to time there will always be a powerful united dynasty in China, but after fall of Western Roman Empire, it completely disintegrated.
However, because of prestige of Roman Empire, any promising ancient European emperor, regardless of his former origin, whether or not he was called "barbarian" by Romans, wanted to restore glory of Roman Empire, calling "Roman Emperor" title is considered highest honor. Of course, some people felt that title "Roman Emperor" was not enough, so they added word "Saint" and became "Holy Roman Emperor".
In fact, this is equivalent to many regimes named after "Han" in Chinese history. With exception of a few such as Liu Bang and Liu Bei, most of others were created by alien races. The reason is that in eyes of foreign races such as Huns, title "Han" has an exclusive honor.
In this historical and cultural atmosphere, Russia, one of three largest European barbarians in eyes of Roman Empire, called itself "Third Roman Empire".
The problem is that Chinese pay attention to integrity of name, and Westerners to a certain extent also pay attention to it. If they claim to be heirs of Roman Empire, there must always be a source of legal authority, so where is legal authority of self-proclaimed "Third Roman Empire" of Russia??
Before answering this question, let's take a look at legal source of "Holy Roman Empire" created by Germans. In 962, "father of Germany" Otto sent troops to Rome. With blessing of power, Pope formally crowned him "Emperor" and "Augustus" and then signed with Pope "Agreement of Otto's Privileges". necessary, Otto defends Pope's status, and Pope recognizes Otto's status. Thereafter, Otto married an Eastern Roman Empire and Princess Diofano of Eastern Roman Empire married Otto II, further establishing legal order of Holy Roman Empire.
The legal source of "Third Roman Empire" in Russia is similar to that of "Holy Roman Empire" - it is also right to inherit by marrying a princess. After Ottoman Empire passed to Eastern Roman Empire, Sophia Paleorog, Princess of Eastern Rome, was exiled to Rome, Italy. At that time, Pope hoped to unite Catholicism and Orthodox Church (the faith of Slavs), so he married her to Russian Tsar.
In Western culture, women, even emperor's nieces, etc., have right to inherit throne, because Russia received right to inherit Eastern Roman Empire by virtue of Sophia Palaeorogus, that is, "Third Rome" legal order.
Of course, having legal status does not mean that you can have it. The key is in place. Ultimately, this is equivalent to buying an entrance ticket. As Russia grew stronger and stronger, their ambitions exploded, and they always wanted to capture Constantinople and restore glory of "Third Rome", which is also one of key reasons for centuries-old enmity between Russia and the Ottoman Empire.
In general, legal system of so-called "Third Roman Empire" in Russia actually originated from fallen princess, who was behind Pope's plan to unite Catholicism and Orthodox Church.
An entrenched Russia has a "ticket to become Roman Empire" so is using it to take advantage of it. On one hand, she is despised by Western Europe and hopes to get title of "Rome" to gild herself; a tendency that longed to seize lands of Ottoman Empire and hoped to gain access to sea in south.