Fill in the blanks. In the mid-1800s, Europe’s c society was thriving and the workers were treated horrifyingly. So a workers’ group called the league was set up, and they asked Karl and Friedrich to come up with a plan for the workers. What they wrote was known as the . From these ideas, the party was set up in Russia, led by Vladimir . This group led a revolution in October 19 and overthrew the unjust tsar . When this leader, Vladimir died in 1924, there was a bitter rivalry between and , over who should take over. ended up gaining power and he ran his rival out of the country. He then began his regime of terror. All who opposed him were arrested by his secret police, known as the , and it only ended with his death in 19 .