I've just been rereading a book published in Rotherham about Tommy James who was in Spain

A lion of a man ed Brian Lewis & Bill Gledhill . In Pounded Earth TJs memoir p68 he mentions waiting to go to Brunete in June 37 thousands of men stretched outon tehbgarss, uncannily quiet 'suddenly the silence was broken by the strains of Tipperary coming from the British lines followed by a medley of music hall songs. Soon all the Brigade was singing, ech man in his particular tongue concluding with The Internationale. That night before the battle thousands stood u and sang. That was after the slaughter at Jarama earlier in the year.
On p 91 after the terrible onslaught at Brunete he mentions listening to Danny Boy being sung by an Irish Comrade in the moonlightand thinking back to the earlier mass sing on night of July 5th 1937

The power of song and the resilience of young men!