There was/is a Folkways album called 'Songs of the Spanish Civil War,' recorded at the time the war was going on in the 1930s. One side is Pete Seeger and some other singers (Almanacs?) doing a number of songs including The 15th Brigade. The other side has Ernst Busch singing (live from the front I believe) 'Six Songs for Democracy' including The Peat Bog Soldiers and Hans Beimler, and at one point the sound of gunfire can be heard in the background.

Padre