Thieves World was the name given to the direct predecessor of the Russian mafia. The organization began in czarist Russia, where, at the time, all property was considered owned, albeit indirectly, by the czar. Therefore, felonies were not only crimes, they were attacks against the state. Therefore, to unleash their pent-up anger at the inept government while at the same time turning a profit, people began stealing and committing other crimes. These thieves eventually became united under a mysterious brotherhood of like-minded individuals. Thus, Thieves World was born.
Thieves World eventually evolved into an entire underground society with its own complicated customs and traditions. Chief among its rules was to never sell out to the government. Members distiguished themselves from one another using an elaborate series of tattoos. A leader had certain markings, an enforcer another set, etc.
This subculture remained a part of Russian daily life up until the Bolshevik Revolution in the early Twentieth Century. The Communist government saw Thieves World as a threat because of its anti-government stance and viciously persecuted its members. The persecution only worsened under Stalin, who sent many of its members to the gulags, those he didn't have executed at least. However, Thieves World did continue on in the prisons.
But by the end of WWII, it was hardly recognizable as the old organization due in part to the Bitch Wars, a series of prison riots immediately following WWII between Thieves World inmates. They were caused by Stalin, who, due to a man-power shortage, offered the Thieves World members pardons if they agreed to serve in the military against the Germans during the war. However, Stalin reneged on his end of the bargain and immediately after the war ended re-imprisoned the former inmates. The problem was that the inmates who had refused to serve in the military believed that the ones who did serve, called "bitches" by the inmates, had broken the most sacred rule of the culture; they had sold out to the state. Therefore, they were punished by the inmates in a series of brutal killing sprees within the prisons, actually encouraged by the Soviet government as a way of winnowing down the prison population. Due to both the Bitch Wars and the strain of prolonged imprisonment inflicted upon most of its members, Thieves World ended up evolving into a new organization. What emerged was even more ruthless than its predecessor and came to be known as the Russian mafia.