(Reuters) – Russian forces fired missiles at several Ukrainian cities and landed troops on its south coast on Thursday, right after Russian President Vladimir Putin authorised what he called a special military operation in eastern Ukraine. Here is a timeline of the main events in Ukraine’s political history since it won independence from Moscow in 1991. 1991: Leonid Kravchuk, leader of the Soviet republic of Ukraine, declares independence from Moscow. In a referendum and presidential election, Ukrainians approve independence and elect Kravchuk president. 1994: Leonid Kuchma beats Kravchuk in a…