In March 1917, during the February Revolution Nicholas II abdicated both for himself and on behalf of his son, ending the Russian monarchy and over three hundred years of Romanov dynastic rule. referring to the three major developments in the political history of Russia of the early 20th-century.
In September and October 1917, German troops invaded the West Estonian archipelago and threatened Petrograd with bombardment and invasion.
Established in 1762, the Commission of Stone Buildings of Moscow and Saint Petersburg ruled that no structure in the city can be higher than the Winter Palace and prohibited spacing between buildings.During the reign of Catherine the Great in the 1760s–1780s, the banks of the Neva were lined with granite embankments.By 1716 the Swiss Italian Domenico Trezzini had elaborated a project whereby the city centre would be located on Vasilyevsky Island and shaped by a rectangular grid of canals.The project was not completed, but is evident in the layout of the streets.During its first few years, the city developed around Trinity Square on the right bank of the Neva, near the Peter and Paul Fortress.
However, Saint Petersburg soon started to be built out according to a plan.
But four years later, in 1732, under Empress Anna of Russia, Saint Petersburg was again designated as the capital of the Russian Empire.
It remained the seat of the Romanov dynasty and the Imperial Court of the Russian Tsars, as well as the seat of the Russian government, for another 186 years until the communist revolution of 1917.
Many monuments commemorate the Russian victory over Napoleonic France in the Patriotic War of 1812, including the Alexander Column by Montferrand, erected in 1834, and the Narva Triumphal Gate.
In 1825, the suppressed Decembrist revolt against Nicholas I took place on the Senate Square in the city, a day after Nicholas assumed the throne.
By the 1840s, neoclassical architecture had given way to various romanticist styles, which dominated until the 1890s, represented by such architects as Andrei Stackenschneider (Mariinsky Palace, Beloselsky-Belozersky Palace, Nicholas Palace, New Michael Palace) and Konstantin Thon (Moskovsky railway station).