Uncovering Key Spanish Civil War Small Arms

Which models of small arms were used in the Spanish Civil War? This note makes a start at answering that question, although it may well be that the question can never be fully answered. Arms purchases were particularly chaotic on the Repulican side, and the records of many of those purchases are undoubtedly lost. On the Nationalist side, the historic record tends to be on the foreign armed forces sent to Spain (the Italian Corpo Truppe Volontaire and the much smaller German Condor Legion), and not on small arms deliveries. Records of these deliveries likely exist in Spanish, German, and Italian archives but I have found so far no in-depth study of them.