The song about football becoming the essence of life had been composed for the German World Cup team of 1974. It was the first of a whole series of World Cup songs published every four years.
It is sung by a boy goup – consisting of the national team. Among the singers are several German all time football heroes: Sepp Maier, Franz Beckenbauer, Paul Breitner, Uli Hoeness, Berti Vogts and Gerd Müller.
The title wants to address everybody: footballers, fans, the whole country.
In the middle of the song, the national team stops singing lyrics and switches to

la la la la la la la la.

No matter what state of euphoria has gripped the fans: this part everybody can sing along.
Thus, music creates a sense of community.
It is similar to a kind of march – with lots of brass. Marches are music for the open air, often played in a military context. For both reasons, it is perfectly suitable for a stadium.
Fan chants for good reasons sometimes are described as battle cries.
What about the battle cry in this song?

Ha! Ho! Heja Heja He!

Fan-Fact

Part of the idea why the song was launched had been to cover the considerable expenses of the 1974 World Cup in Germany. The German Football Association scored a winner: “Fußball ist unser Leben” sold like hot cakes – or like sausage and beer. And it accompanied the team on its way to championship.