Timeline: Events in Ukraine's political history since 1991

KIEV (Reuters) - A comedian with no political experience is tipped to win the first round of Ukraine's presidential election on Sunday amid discontent over corruption and five years of war against pro-Russian separatists in the east of the country.

Here is a timeline of the main events in Ukraine's political history since the country's independence in 1991.

* 1991: Leonid Kravchuk, leader of the Soviet republic ofUkraine, declares Kiev's independence from Moscow. In areferendum and presidential election Ukrainians approveindependence by 92 percent and elect Kravchuk president. * 1994: Kravchuk loses presidential election to LeonidKuchma in elections deemed largely free and fair by observers. * 1999: Kuchma is re-elected in 1999 in a vote riddled withirregularities. Appoints a new prime minister: ViktorYushchenko, former chairman of the national bank. * 2000: Journalist Georgiy Gongadze is murdered in whatbecomes one of post-Soviet Ukraine's most notorious crime cases.The incident epitomises the sleaze and violence of the Kuchmaera and leads to street clashes. * * 2001: Kuchma fires his deputy prime minister for energy,Yulia Tymoshenko. Known as the 'gas princess' for her designerclothes and involvement in the gas industry, she is fired aftercharges of forgery and gas smuggling in her previous businessare brought against her. Tymoshenko spends a month in detention.She denies the charges as a political witchhunt and is latercleared by the courts. * * 2004: Prime Minister Viktor Yanukovich, the pro-Moscowestablishment candidate, takes on pro-European opposition leaderViktor Yushchenko in a presidential election. After a toxic race- during which Yushchenko's face is disfigured in a poisoningattempt - Yanukovich is declared winner. But claims ofvote-rigging trigger mass street protests known as the OrangeRevolution, forcing a re-run of the vote. In a stunningreversal, Yushchenko is declared the new winner. * 2005: Yushchenko comes to power in January, launching apro-Western agenda that promises to modernise Ukraine and leadit out of the Kremlin's sphere of influence, towards NATO andthe European Union. He appoints Tymoshenko his prime minister,after her fiery speeches supporting the Orange Revolution gainher a dedicated following. But she soon falls out with thepresident and is sacked after less than eight months in officeafter much infighting. * 2006: Following a row with Moscow over gas supplies, aparliamentary election produces a majority for Yanukovich'spro-Moscow party. President Yushchenko accepts his rival asprime minister. Yanukovich gradually secures control over theeconomy and key government jobs. * 2007: Parliamentary elections are held again, pro-"Orange"parties secure a tiny majority. In December, parliament votes inTymoshenko as prime minister for a second stint. * 2009: Amid another gas pricing row with Moscow, Tymoshenko starts negotiations with Russian Prime Minister Vladimir Putinto resolve a crisis that threatens to leave Europe withoutenergy supplies. * * 2010: A fresh presidential election brings Yanukovich backto power, defeating Tymoshenko for the top job. His comeback isbased on financial support from wealthy industrialists ineastern Ukraine, as well as promises to fight poverty. Russiaand Ukraine clinch a new gas pricing deal, in exchange for anextension of a lease for the Russian navy in a Ukrainian BlackSea port. * 2011: Tymoshenko is sentenced to seven years in prisonover her 2009 gas deal with Russia on charges of abuse of power.She denies any wrongdoing and accuses Yanukovich of pursuing apolitical vendetta against her and her supporters. * 2013: Yanukovich's government suddenly announcessuspension of trade and association talks with the EU inNovember and opts to revive economic ties with Moscow,triggering months of mass rallies in Kiev. Protests reach800,000 by end-2013. * * 2014: Protests, largely focused around Kiev's Maidansquare, turn increasingly violent. Dozens of protesters arekilled. In February, Ukraine's parliament votes to removeYanukovich, who flees. Tymoshenko is released from jail. Withindays, armed men seize parliament in the Ukrainian region ofCrimea and raise the Russian flag. Moscow annexes the territoryafter a referendum which shows overwhelming support in Crimeafor joining the Russian Federation. In April, pro-Russianseparatists declare independence and fighting breaks out ineastern Ukraine. In May, businessman Petro Poroshenko wins apresidential election with a pro-Western agenda. In July, amissile brings down the MH17 passenger plane, with the weaponused traced back by investigators to Russia, something Russiadenies. * 2017: An association agreement between Ukraine and theEuropean Union is passed, opening both markets for the freetrade of goods and services, as well as visa-free travel to theEU for Ukrainians. * 2018: A naval clash between Russian border guards andUkrainian ships in the Kerch Strait near Crimea leads Poroshenko to declare martial law. * 2019: The Ukrainian Church secures autonomy from theRussian Orthodox Church, angering the Kremlin.

The first round of voting in Ukraine's presidential election will take place on Sunday. If no candidate secures a majority, the election will move to a second-round run-off on April 21.

(Compiled by Polina Ivanova; Editing by Gareth Jones)