Short answers, pulled from the story.
The Russian Empire officially began in November 1721 when the Governing Senate and Synod invested Tsar Peter I with the titles of Imperator of all Russia. This formal declaration transformed a centuries-old tsardom into an empire that would dominate northern Eurasia for nearly two hundred years.
Through the Treaty of Nystad signed in 1721, Peter acquired four provinces south and east of the Gulf of Finland to secure access to the Baltic Sea. This treaty ended the Great Northern War after Sweden asked for peace due to exhaustion from decades of conflict.
By the end of the 19th century, the area covered about twenty-two point eight million square kilometers or almost one-sixth of Earth's landmass. The empire also conquered Central Asia throughout the late 19th century taking much of Russian Turkestan by 1865 and continuing to add territory as late as 1885.
Serfdom was abolished on the 3rd of March 1861 when Alexander II decided to abolish serfdom from above with ample provision for landowners rather than wait for revolution to destroy the system from below. The reform required freed peasants to pay a special lifetime tax to the government instead of receiving their lands as gifts.
In January 1905 Father Georgy Gapon led an enormous crowd to the Winter Palace presenting a petition to the emperor when soldiers opened fire killing hundreds during the Bloody Sunday incident. Russian masses became so furious over the massacre that a general strike was declared demanding a democratic republic.
The Russian Revolution began on the 2nd of August 1914 when Emperor Nicholas II declared war on Germany from the balcony of the Winter Palace after Austria-Hungary cut diplomatic ties July 28 following the assassination of Archduke Franz Ferdinand. International Women's Day strikes organized by factory workers in Petrograd on the 3rd of March 1917 followed thousands of people taking streets to protest food shortages and demand Russia withdraw from the war before the emperor was deposed.