The "Russian world" (Russian: русский мир, romanized: rússkiy mir) is a concept and a political doctrine usually defined as the sphere of military, political and cultural influence of Russia. It is a vague term, mostly used to refer to communities with a historical, cultural, or spiritual tie to Russia. This can include all ethnic Russians and Russian speakers in neighboring states, as well as those who belong to the Russian Orthodox Church. The concept of the "Russian world" is linked to Russian neo-imperialism. President Vladimir Putin established the government-funded Russkiy Mir Foundation to foster the idea of the "Russian world" abroad. The concept is sometimes also called the Pax Russica, as a counterweight to the Pax Americana after WWII.

Philologist Andrey Desnitsky [ru] analyzed the National Corpus of the Russian Language and established that the expression "Russian world" was used only sporadically before 1930s. Later the term started being used more frequently, as he wrote, "They seem to be characteristic of the romantic European nationalisms of that period when people within the same nation state (or longing for such a state, as was the case in Germany) started to look for a common identity based on ethnicity and culture. Similar concepts can be found in other languages, like Deutschtum in German or Hispanidad in Spanish. Still later, up until World War I the term became a commonplace, mostly used as an apposition to other nations, "usually without any jingoism". After the Russian Revolution the expression became nearly obsolete, only to resurface in Kremlin propaganda since the early 21st century.

The "Russian world" is a vaguely defined term, mostly used to refer to communities with a historical, cultural, or spiritual tie to Russia. This can include all ethnic Russians and Russian speakers in neighboring states, as well as those who belong to the Russian Orthodox Church. Its proponents believe Russia is a "unique civilization" and a bastion of "traditional values" and national conservatism. The "Russian world" idea is linked to Russian neo-imperialism. Jeffrey Mankoff of the Institute for National Strategic Studies says that the "Russian world" embodies "the idea of a Russian imperial nation transcending the Russian Federation's borders" and challenges "neighboring states' efforts to construct their own civic nations and disentangle their histories from Russia". A number of observers see the "Russian world" concept as revanchist, with the goal of restoring Russia's borders or its influence back to that of the Soviet Union and the Russian Empire.

In the 1990s, Russian neo-fascist philosopher Aleksandr Dugin began writing about Russia as a unique Eurasian civilization. Dugin was later an adviser to Russian president Vladimir Putin. Other authors behind the development of the concept in post-Soviet Russia include Pyotr Shchedrovitsky [ru], Yefim Ostrovsky, Valery Tishkov, Vitaly Skrinnik, Tatyana Poloskova and Natalya Narochnitskaya.^{[citation needed]} In 2000, Shchedrovitsky presented the main ideas of the "Russian world" concept in the article "Russian World and Transnational Russian Characteristics", among the most important of which was the Russian language. Andis Kudors of the Woodrow Wilson International Center for Scholars, analyzing Shchedrovitsky's article, concludes that it follows ideas first laid out by the 18th century philosopher Johann Gottfried Herder about the influence of language on thinking (which has become known as the principle of linguistic relativity): those who speak Russian come to "think Russian", and eventually to "act Russian".

Observers describe the concept as a tool of Russian soft power. According to assistant editor Pavel Tikhomirov of Russkaya Liniya [ru], many Ukrainians see the "Russian world" as neo-Sovietism under another name. The Financial Times described the "Russian world" as "Putin’s creation that fuses respect for Russia's Tsarist, Orthodox past with reverence for the Soviet defeat of fascism in the Second World War. This is epitomised in the Main Cathedral of the Russian Armed Forces, 40 miles west of Moscow, opened in 2020".

The Economist says that the "Russian world" concept has become the basis of a crusade against the West's "liberal" culture and has fed a "new Russian cult of war". It says that Putin's regime has debased the "Russian world" concept with a mixture of obscurantism, Orthodox dogma, anti-Western sentiment, nationalism, conspiracy theory and security-state Stalinism.

Eventually, the idea of the "Russian world" was adopted by the Russian government under Vladimir Putin. In 2001, he said "The notion of the Russian World extends far from Russia's geographical borders and even far from the borders of the Russian ethnicity".

Putin visited the Arkaim site of the Sintashta culture in 2005, meeting the chief archaeologist Gennady Zdanovich. The visit was widely covered in Russian media, which presented Arkaim as the "homeland of the majority of contemporary people in Asia, and, partly, Europe". Nationalists called Arkaim the "city of Russian glory" and the "most ancient Slavic-Aryan town". Zdanovich reportedly presented Arkaim to the president as a possible "national idea of Russia", a new idea of civilisation which Victor Schnirelmann calls the "Russian idea".