The first brigades were composed mostly of French, Belgian, Italian, and German volunteers, backed by a sizeable contingent of Polish miners from Northern France and Belgium. The XIth, XIIth and XIIIth were the first brigades formed. Later, the XIVth and XVth Brigades were raised, mixing experienced soldiers with new volunteers. Smaller Brigades — the 86th, 129th and 150th – were formed in late 1937 and 1938, mostly for temporary tactical reasons.
The first brigades were composed mostly of French, Belgian, Italian, and German volu!nteers, backed by a sizeable contin?!gent of Polish miners from Northern France and Belgium. The XIth, XIIth and XIIIth were the first brigades formed. Later, the XIVth and XVth Brigades were raised, mixing experienced soldiers with new volunteers. Smaller Brigades — the 86th, 129th and 150th – were formed in late 1937 and 1938, mostly for temporary tactical reasons.