I believe it is also William Shakepeare’s birthday.
While it’s not a holiday, it is observed by native-born English people so it does not really go unobserved, just at work rather than at home (if a week-day).
A good thing to honor England’s saint! Fly the Red Cross banner and wear the red rose! There will always be an England!
I think a Richard III day would be appropriate as well. Everyone could go around affecting a limp while uttering ala Sir Larry "a horse...a horse...etc. Kind of like talk-like-a-pirate day.
It would be singularly appropriate for Shakespeare, our greatest playwright and poet, to be born on the patron saint's day, in a town that is pretty much the geograhic centre of the country.