Charter 77 was created in 1976 as a response to the Plastic People's of the Universe trial by the government. Vaclav Havel and Jiri Nemec participated in the trial, and were inspired by the bravery of the students.
The Charter itself was created in response to the governmnet oppression following the Prague Spring of 1968, and spoke out against he government. This was the first public effort since 1968 where people stood up again to fight.
Regardless of the message the Charter members were trying to get out, the initial movement was still very small. There were less than 20 original signatories, and people were even discouraged from signing due to the threat of arrest. Many citizens did sympathize with the movement, but they didn't feel as though it was worth the risk at that time.
Havel and the other members continued to fight through the Charter until 1989 when it was transformed into the Civic Forum. Over the years, this group served as an inspiration to others who were also finding their voice.