In 2004, The Criterion Collection released one of the first high-quality versions of Charade on DVD. It was also re-released on blu-ray in 2010.  Every release from The Criterion Collection includes a special booklet that has an essay about why their films are historically important. Linked below is Criterions essay about Charade and it’s historical significance.

https://www.criterion.com/current/posts/64-charade-the-spy-in-givenchy