Russian Empire
Though the Empire was only officially proclaimed by Tsar Peter I following the Treaty of Nystad (1721), some historians would argue that it was truly born either when Ivan III of Russia conquered Veliky Novgorod in 1478, or when Ivan the Terrible conquered the Khanate of Kazan in 1552. According to another point of view, the term "Tsardom", which was used after the coronation of Ivan IV in 1547, was already a contemporary Russian word for empire.
List of Russian rulers
The land that is today known as Russia was populated by various East Slavic peoples from before the 9th century. The first states to exert hegemony over the region were those of the Rus' people, a branch of Nordic Varangians who entered the region occupied by modern Russia sometime in the ninth century, and set up a series of states starting with the Rus' Khaganate circa 830. Little is known of the Rus' Khaganate beyond its existence, including the extent of its territory or any reliable list of its Khagans (rulers). Traditionally, Russian statehood is traced to Rurik, a Rus' leader of Holmgard (later Novgorod, modern Veliky Novgorod), a different Rus' state. Rurik's successor Oleg moved his capital to Kiev, founding the state of Kievan Rus'. Over the next several centuries, the most important titles were those of the Grand Prince of Kiev and Grand Prince of Novgorod whose holder (often the same person) could claim hegemony. By the early 11th century the Rus' state had fragmented into a series of petty principalities which warred constantly with each other. In 1097, the Council of Liubech formalized the federal nature of the Russian lands. By the 12th century, the Grand Duchy of Vladimir became the dominant principality, adding its name to those of Novgorod and Kiev, culminating with the rule of Alexander Nevsky. After Alexander Nevsky, the region once again broke up into petty states, though the Grand Duchy of Moscow, founded by Alexander Nevsky's youngest son Daniel, began to consolidate control over the entire Russian territory in the 15th century. Following the Mongol conquests of the 13th century, all of the Russian principalities paid tribute to the Golden Horde, effectively operating as vassals of the Mongol state. The Russians began to exert independence from the Mongols, culminating with Ivan the Great of Moscow ceasing tribute to the Horde, effectively declaring his independence. Last Grand Prince of Moscow Ivan the Terrible assumed the title Tsar of All the Russias in 1547.