“Yes!!!” Ukrainian President Petro Poroshenko tweeted.
“An unbelievable performance and victory! All of Ukraine gives you its heartfelt thanks, Jamala.”
Prime Minister Volodymyr Groysman tweeted his congratulations, adding “glory to Ukraine!”
The 32-year-old winner is a member of the Muslim Tatar minority of Crimea who saw her great-grandmother deported along with 240,000 others by Stalin in the penultimate year of World War II.
Jamala’s poignant song opens with the harrowing line: “When strangers are coming, they come to your house, they kill you all and say, ‘we?re not guilty, not guilty’.”
But the memories of that horror have been revived by Russia’s seizure of Crimea several weeks after a pro-EU revolt ousted Ukraine’s Moscow-backed president in February 2014.
Russia had earlier protested Ukraine’s entry in the contest because of its “political” subtext — a violation of the contest’s rules.
But Eurovision ruled that Jamala was “historical” in nature and allowed her song “1944” to compete.
One of the 2014 revolution’s leaders wrote that it would be fitting for Ukraine — which will host the event next year thanks to Jamala’s win — to stage the contest in Crimea itself.
“Justice would be served if the next Eurovision is held in Jamala’s historical homeland — Ukraine’s Crimea,” Mustafa Nayyem tweeted.