Was the Winnipeg General Strike successful?

Yes, but not immediately. The workers ended up going back to work once the strike ended and they had to sign waivers saying they would not join any union and they were punished. Some workers were fired, some lost their pension rights, etc. But the next year (1920), 11 labourors won seats in the Manitoba government, 4 of which were strike leaders. With their help, 20 years later, things improved. Now, we have good wages and good working conditions all thanks to the Winnipeg General Strike.