TIL that Sir Nicholas Winton helped rescue 669 Czhechoslovak children from the holocaust

Whilst watching a movie (and looking things up on wikipedia after).

More than 350'000 jews lived in Czechoslovakia before WW2. Approximately 18'000 children were sent to death camps, of which fewer than 200 survived. Meanwhile, this man helped save 669 children.

For comparison, approximately 7'000 jewish people live in Czechia and Slovakia today.

https://en.wikipedia.org/wiki/Nicholas_Winton

Feel free to add more interesting context in the comments, would love to learn more!