Rampant was written in the autumn of 1997. A year before Räihälä was at the UNM festival in Copenhagen and happened to hear how the violinist and composer Jaakko Kuusisto trained some unpitched tones that he called "fart tones". These are done with very slow and hevy bowing on the g-string. The resulting tone is usually a minor seventh or an octave lower than the written note. However, these tones are extremely difficult to control. Räihälä decided to write a piece for the violin, where he would use this effect. Kuusisto, thinking of his brother Pekka, suggested that Räihälä would add another violin and so piece ended up as a composition for two solo violins.

In the end there is only a short passage in the middle of the piece where the fart tones are to be played. The name Rampant was fetched from a football commentary by BBC's John Motson, who once enthused "It's a rampant Everton now!". Hearing this, Räihälä decided to use that as the title for the work, especially because he wanted to write fast and rampant music. In the work there are a couple of calm moments between all the rampage. Rampant was premièred by Kuusistos in August 1998 and was an instant success. It has become one of Räihälä's most successful works and has been played several times at various festivals during the years.