A Cossack republic emerged and prospered during the 17th and 18th centuries, but its territory was eventually split between Poland and the Russian Empire, and later merged fully into Russia.
The Goths stayed in the area but came under the sway of the Huns from the 370s AD.
In the 7th century AD, the territory of eastern Ukraine was the centre of Old Great Bulgaria.
In the 2000s, the government began leaning towards NATO, and a deeper cooperation with the alliance was set by the NATO-Ukraine Action Plan signed in 2002.
It was later agreed that the question of joining NATO should be answered by a national referendum at some point in the future.
Excluding Crimea, Ukraine has a population of about 42.5 million, making it the 32nd most populous country in the world.
The territory of modern Ukraine has been inhabited since 32,000 BC.
The first of these periods occurred briefly during and immediately after the German occupation near the end of World War I and the second occurred, also briefly, and also during German occupation, during World War II.
However, both of these first two earlier periods would eventually see Ukraine's territories consolidated back into a Soviet republic within the USSR.
Ukraine is a unitary republic under a semi-presidential system with separate powers: legislative, executive and judicial branches. Taking into account reserves and paramilitary personnel, 77.8 percent of whom are Ukrainians "by ethnicity", followed by a sizeable minority of Russians (17.3 percent) as well as Georgians, Romanians/Moldovans, Belarusians, Crimean Tatars, Bulgarians and Hungarians.