Mats Wester (born September 1, 1964 in Botkyrka, Sweden) is a musician and plays the nyckelharpa. Mats studied at Adolf Fredriks Musik Skola in Stockholm. Together with the singer Håkan Hemlin he operates the musical group Nordman. During Nordman's long pause Mats created another group together with Py Bäckman (lyrics) and Elenor Ågeryd (vocals). Mats has also written a song for the group Garmarna "En gång ska han gråta" (Once he will cry). As many times before Py Bäckman wrote the lyrics to the song.
https://en.wikipedia.org/wiki/Mats_Wester