Hooooo boy... nothing says "light summer reading" like a history of Ukraine.
"The Gates of Europe" is a fairly traditional telling of the land and people that have, at some times, but not at others, been referred to as Ukraine and Ukrainians. I say "fairly traditional" as, while it's mostly a chronological narrative of events that occur over time in a reasonably specific patch of geography, Ukraine has not been an independent, sovereign state for much, nay, most of that time, and the people we today identify as Ukrainians often weren't in the past.
It's a bit of a muddle.
Due to Ukraine's anomalous status throughout most of history, its story is of necessity thickly intertwined with those of the other nations of which Ukraine has been part over the centuries. To his credit, Plokhy keeps a pretty tight focus on the Ukrainians and only brings in the Poles, Austrians, Russians, etc., as much as is needed to put the Ukrainian narrative into proper context. More importantly, he spends a good amount of time covering what each period itself thought it meant to "be Ukrainian", going into detail on contemporary academic and literary trends and arguments that were completely unknown to the vast majority of peasants whose identity was being argued over. This detail spent on the arguments of tiny elites isn't, I'm sure, by choice; as ever with history, nobody cared to write down much about what the vast majority of people felt about these things at the time. So Plokhy is just working with what he has here.
The book covers well the various bases on which a putative Ukrainian "nationhood" has been claimed over time; religion, language, Cossack-ness, the ancient Kievan kingdom of Rus... part of the difficulty in writing a book such as this is that there is not, even today, any agreement that characteristics X, Y and Z being present in person A makes them a Ukrainian as opposed to a Russian or a Belarusian. There are diehard Ukrainian nationalists today who can only speak Russian, for example. Likewise, there are Uniate Church-adhering Ukrainian speakers who consider themselves fully Russian, and who would like their chunk of the nation-state of Ukraine to revert to the Rodina as soon as possible.
Plokhy does not place value judgments either way, an admirable locking down of whatever bias he may actually feel on the issue; it's a pretty dry, straight-forward narrative that does not push a belief that Ukraine is a unique, distinct culture/nation/person-type separate from Russia in any overbearing fashion. That he wrote a book about Ukrainian history in the first place makes his point of view clear; overselling the point would probably just turn the rather intense partisans on either side of the divide off from the get-go (a point which online reviews of this book make sadly clear).
I enjoyed the book, though I found Plokhy's studious devotion to detachment to have rendered it rather dry at times. There aren't many English-language histories that cover the whole of the Ukrainian story in one volume without including a lot of non-Ukrainian narrative, so I'm glad "The Gates of Europe" exists. If you just want to try and wrap your head around Ukraine's deal, you'd easily do worse than to pick this one off of the shelf.