Kristian Kostov, 17, has become the youngest contestant in Eurovision to reach this stage.
Runner-up Kristian Kostov of Bulgaria wasn't short on feeling - his powerful song "Beautiful Mess" was awash in melodrama, the singer appearing nearly wrung out by romantic turmoil.
Ukrainian President Petro Poroshenko on Saturday cancelled his planned appearance at the Eurovision Song Contest final in Kiev after a shelling attack in the war-torn east reportedly killed four civilians. Salvador Sobral was given a huge hero welcome to what he commented "I'm not a hero, Ronaldo is". Bulgaria has participated in Eurovision for 11 times.
The early favorite, Francesco Gabbani of Italy, finished sixth.
Eurovision, in its 62nd year, is aimed at apolitical entertainment.
This year's contest was hosted by Kiev, the capital of Ukraine, and it was not without controversy.
Russian Federation - one of Eurovision's heavy hitters - is tied with Sweden for the most top-five finishes this century.
Kiev barred Russia's singer Yuliya Samoilova because she had illegally entered Crimea to perform there after Moscow's disputed annexation of the peninsula from Ukraine.
"In response, Russia's state-owned Channel 1 television is refusing to broadcast the contest, replacing Saturday's final with a screening of the film "Alien". Samoylova has already been announced as Russia's Eurovision candidate for 2018.
The song attained 758 points, ahead of Bulgaria in second on 615 points and Moldova in third on 374 points, and way up from last year's victor Jamala for Ukraine, which received 534 points.
This year, Ukraine has used the contest to take tentative steps to soften the climate of homophobia prevalent in the ex-Soviet Union.
From its launch with seven countries, Eurovision has grown to include more than 40, including non-European nations such as Israel and, somewhat controversially, far-off Australia, where the event has a huge fan following.
Eurovision has a major following, and it has helped to boost the careers of many performers - including Sweden's ABBA which won in 1974 with the song "Waterloo".