Why was Pope Kiril called 'a Russian Pope?'

Yes, I wondered that myself. I think it was just an American thing, since the Ukraine fell under the thumb of the USSR, and we paint (too much) with a broad brush, calling him Russian. It's like when I say I am an American. I'm from Central Upstate New York, but I refer to myself as an American.
What I always found interesting, and didn't know this until recently (thank you Robert Osborne) is that the film was written to take place in the 1980s. As a scholar of the church and of sociology, I find that mannerisms that were normal in the 60s and a faint memory in the 1980s, both in the church and in the modern world. My favorite is the cocktail party. I can remember my father telling me that, at 6:30pm, he'd take off his suit, shower, and have to put on a black tie for dinner. I was born in 1985 and much to my displeasure that was LONG gone by then (although making a slight come back). Also the geo-politics are fascinating. What would've happened if Mao died before “détente”, and someone far less devoted to himself and more to the revolution came into power?
It's a good film, all around.

At the time the film was made, as well as the era in which it was set, Ukraine was part of the Soviet Union, which was often erroneously referred to as Russia. If I'm not mistaken, the only person who refers to Pope Kiril as a Russian is the American television reporter played by David Janssen, and he said it in a slightly pejorative way. I suspect they had him do that on purpose to illustrate the ill feeling that existed between the Americans and the Soviets in that era.

"Good relations with the Wookies I have." (Yoda, Star Wars: Episope III)

I doubt if anyone outside Ukraine, barring bitter expatriates and petty nationalists, cares greatly.

Since Janssen was apparently supposed to be the Vatican reporter for a US TV network, yes, he should have taken the trouble to get it right.

It was not accurate to call Kiril a "Russian Pope," but it would have been to call him a "Soviet Pope."



================

4) You ever seen Superman $#$# his pants? Case closed.

He was, in fact, a "Soviet" since the term "Russian" was really not applicable again until the Soviet Union unraveled.

Even as I was growing up at the height and decline of the Cold War, the terms Soviet and Russian were interchangeable, in the UK as well as America. England's greatest football triumph, the 1966 World Cup victory, was aided by the man forever remembered as "the Russian linesman", who gave a goal which had not actually gone over the line. After the Soviet Union collapsed, those of us who wished to look up the details of the incident would be surprised to discover that the "Russian" linesman was not Russian at all, but a native of that mysterious Caucasian country Azerbaijan.