We used to call it THE Ukraine. But that definite article has the odd effect of belittling a place, or seeming to. The Lebanon, The Argentine, The Levant...in each case the definite article implies that the place we're talking about is just a section of another place, rather than a country in its own right.  These days, with the exception of the Levant - which really is a region rather than a country - we've dropped that definite article. But I remember how when I was still at the BBC a Ukrainian colleague used to get very cross if anyone said, in English, THE Ukraine. Weird when you consider that in UKrainian, just as in Russian, there are no articles, definite or otherwise, at all.

Never mind all that. Ukraine as a country has existed sometimes and sometimes not. It has been subsumed into other countires/empires, and it has had its borders continually fiddled about with.

In the earliest days, the 10th century, Kiev was where a certain Prince Vladimir founded what would one day be called Russian Orthodoxy. Prince of a pagan region he had sent out emissaries to hunt for a unifying religion for his lands because for some reason I cannot fathom he thought they ought to have one. The emissaries gave judaism a try, but it was no fun; they looked at Islam, but you can't drink in Islam; then they stumbled on a Greek Orthodox liturgy in the Aya Sophia in Constantinople, and came rushing back to tell their prince about its unforgettable  beauty. And so it was.

In later times Ukraine has been at the centre of (Russian or Soviet) agriculture and nuclear strength. Dniepropetrovsk (now called Dnipropetrovsk) was at one time a closed city, housing (if that's the word) the Soviet nuclear weapons industry in hangar factories the size of small towns. But after the collapse of the USSR in 1991, when Ukraine became an independent country (no more THE), it agreed to divest itself of that nuclear stockpile. 

In 1994 as part of the Treaty on the Non-Proliferation of Nuclear Weapons Ukraine agreed to give up its simply enormous arsenal of the things that had been Soviet but were now on Ukrainian soil. In return the USA, the UK and Russia signed an agreement called the Budapest Memorandum, under which Ukraine's territorial integrity would be guaranteed by those three signing powers.

Erm...