Why did Gruwu quickly develop into a huge foreign spy network after its establishment?

After the establishment of Gruwu, a huge foreign spy network developed rapidly. This is closely related to the objective conditions and tasks undertaken at that time. The favorable objective conditions at that time were: after the October Revolution, there were more than 4 million foreigners in the central area of the Soviet Union, from Germany, Austria, Hungary, Poland, the Czech Republic, North Korea and Serbia.

Most of these people are prisoners of war and refugees, and more than 300,000 of them signed up for the Red Army. What's more, these people themselves are loyal to Marxism and do not need recruitment review. As long as the military intelligence department gives them some technical training, they can be sent out and become well-covered spies.

Secondly, after the October Revolution, millions of old Russian immigrants scattered around the world. Their main components are Russian princes and nobles, Belarusian officers, capitalists, landlords and so on. Afraid of the Soviet Red Regime, they fled all over the world. Some of these immigrants fled abroad because they did not understand the red regime and listened to the reactionary propaganda of western capitalism and some hostile forces. These immigrants also provided unique conditions for the dispatch of Gruu.