Short answers, pulled from the story.
The Revolution of Dignity, also called the Maidan Revolution or Ukrainian Revolution, took place in February 2014 at the end of the Euromaidan protests. It resulted in the removal of President Viktor Yanukovych by parliament, the restoration of the 2004 constitution, and prompted Russia to occupy Crimea, starting the Russo-Ukrainian war.
Protests began in November 2013 after President Yanukovych refused to sign a political association and free trade agreement with the European Union at a summit in Vilnius, Lithuania, choosing closer ties with Russia instead. Russia had offered a 15-billion-dollar financial package and cheaper gas, while the EU offered 610 million euros but required significant legal and regulatory reforms.
Altogether, 108 civilian protesters and 13 police officers were killed. Most deaths occurred on the 18th through the 20th of February 2014, with 48 protesters shot dead on Instytutska Street in Kyiv on the 20th of February alone. The killed civilians are commemorated in Ukraine as the Heavenly Hundred.
On the 22nd of February 2014, Ukraine's parliament voted 328-0 to remove Yanukovych from office after he secretly fled Kyiv the night before without informing parliament. Oleksandr Turchynov was elected parliamentary chairman and became acting president under the reinstated 2004 constitution. An arrest warrant for Yanukovych was issued on the 24th of February.
According to documents released by former Ukrainian Deputy Interior Minister Hennadiy Moskal, Russian advisers were involved in planning the crackdown on protesters under operations code-named Wave and Boomerang. Ukraine's new security officials later said more than 30 Russian FSB agents had been based at a Security Service of Ukraine compound in Kyiv throughout the protests. The 2-billion-dollar transfer from Russia's financial package was made hours before the police assault was ordered.
The first Yatsenyuk government was formed on the 27th of February 2014 and signed the EU Association Agreement on the 21st of March 2014. The Berkut riot police was dissolved, a lustration law barring former Yanukovych officials from government was enacted, and new presidential elections were held on the 25th of May 2014. Russia occupied and annexed Crimea and backed separatists in the Donbas, starting a wider war.