Actually the song is called Trebaruna (from the celtic "Trebo" - meaning 'home' - and "runa" - meaning 'secret' or 'mystery'), after the Goddess of the House, Battles and Death in Lusitanian mythology. And Viva, in this context, means something like 'Hail!' (it is used as an expression of showing respect and/or joy, that's correct)
Actually the song is called Trebaruna (from the celtic "Trebo" - meaning 'home' - and "runa" - meaning 'secret' or 'mystery'), after the Goddess of the House, Battles and Death in Lusitanian mythology. And Viva, in this context, means something like 'Hail!' (it is used as an expression of showing respect and/or joy, that's correct)