Political messages of any kind are officially banned from Eurovision, but that hasn't stopped them seeping into the famed song contest.
The competition kicked off in Switzerland in 1956, conceived as a way to unite the countries of Europe, then still recovering from the devastation of World War II.
Since then, it has survived despite a number of major conflicts between European nations and several countries disappearing and new ones appearing in their place on its map.
One of the most common complaints about the contest is that is that neighbouring countries, particularly those which are culturally similar, often for vote for each other. Vote-trading between Cyprus and Greece, for example, is common.
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The Scandinavian countries often award each other points, as do some of the nations born out of former Yugoslavia... except Kosovo. The young nation doesn't participate, which according to an official Eurovision spokesperson is in part because RTK (the public broadcaster of Kosovo) is not a member of the European Broadcasting Union (EBU).
But it's more complicated than that. The country can't join the EBU unless it is first a member of the International Telecommunication Union (ITU). And it can't join the ITU until it becomes a member of the United Nations, which is yet another hurdle -- Serbia and Russia have both blocked Kosovo's bid for UN membership.
That didn't stop singer Rona Nishliu from the Kosovar city of Mitrovica finding a loophole in the 2012 Eurovision contest in Azerbaijan. She entered representing neighbouring Albania.
WATCH: Rona Nishliu performs for Albania
The Azerbaijan competiton also drew controversy, with activists using the country's publicity boost to draw attention to the country's human rights record.
Georgia's preferred entry for the 2009 competition was vetoed by the EBU less than a year after the Russian-Georgian War, when their song "We don't wanna Put In" too closely referenced the Russian leader.
WATCH: Georgia's failed entry for the 2009 competition
In 2005, Lebanon made an attempt to field a contestant, but that folded when the national broadcaster refused to air the contest under a ruling that prohibits showing any Israeli content.
Jordan faced a similar problem 27 years earlier. The nation decided to broadcast the show but omitted Israel's entry altogether, running vision of flowers instead of the song. The absence became a problem when Israel went on to win the competition, so the broadcast was stopped, and runner-up Belgium was declared the winner.
WATCH: Israel's winning 1978 song
The question of why Middle Eastern countries including Israel, Jordan and Lebanon are permitted to enter Eurovision is a controversy in itself. It's because Eurovision's geographical boundaries are based on the European Broadcasting Union (EBU), which stretches into the Middle East and North Africa.
Watch Eurovision on SBS ONE:
Semi Final 1 - Fri May 17, 8.30pm
Semi Final 2 - Sat May 18, 7.30pm
FINAL - Sun May 19, 7.30pm
