From http://www.newworldeconomics.com/archives/2011/061911_files/Pages from tim-green.pdf
See Table 4 below, major increases to the gold reserves stored in London and New York, Moscow and Paris took place on the dawn of World War 2.
According to this silver article, from the time of Spain's conquering of the "new world", the value of gold in relation to silver maintained a relatively stable ratio of 15½ over 1. A British pound note could be exchanged at the Bank of England for one gold sovereign (with 7.322 grams of gold) or 20 silver shillings (with 5.655 grams of silver), thus staying close to this ratio, and establishing relative stability with business and government contracts worldwide.
According to this article by Robert Whiston (see section 10a) USSR gold reserves, which had been 7456 metric tonnes in 1935, second only to the US, increased by yet another 510 metric tonnes in 1936 as a result of the
Spain and the USSR had this in common at the outbreak of World War 2, neither reported their holdings to
** End of Report