Jean Sibelius (1865-1957) is the most well known Finnish composer. Here you can find more info about him: http://en.wikipedia.org/wiki/Jean_Sibelius
Jean Sibelius: "Finlandia"
You can find the lyrics from here, they were not part of the original song but later composed. (Finnish, Swedish and English translations):http://lyrics.wikia.com/Jean_Sibelius:Finlandia
Jean Sibelius: "Valse triste"