October 1, 1964: The Free Speech Movement was started at the University of California at Berkeley. One of the most important of the amendments, the first amendment gives the right of freedom of speech.

From the U.S. Constitution

The First Amendment provides that Congress make no law respecting an establishment of religion or prohibiting its free exercise. It protects freedom of speech, the press, assembly, and the right to petition the Government for a redress of grievances.

https://www.whitehouse.gov/about-the-white-house/our-government/the-constitution/

From the U.N. Declaration of Human Rights Preamble

Whereas disregard and contempt for human rights have resulted in barbarous acts which have outraged the conscience of mankind, and the advent of a world in which human beings shall enjoy freedom of speech and belief and freedom from fear and want has been proclaimed as the highest aspiration of the common people,

https://www.un.org/en/about-us/universal-declaration-of-human-rights

https://on-this-day.com/onthisday/thedays/alldays/oct01.htm