We Brits had All Saints Day and All Hallows Eve before America was colonised, but one was a date on the Church Calendar. For the other one maybe you'd secretly peel an apple in a single strip to see the first letter of your true love's name, or look into a mirror at midnight to see his face. It was a 'thing' mostly for teenage girls, I guess, and made of dark stuff, with an element of being nearer to the other worlds, and naughty.
We had Harvest Festival, a good day for celebrating the concept of surviving another year, for having food safely harvested and stored, and again revolving around the Church.
We had a Saint for every Country in the Kingdom - St David for Wales (01 Mar), St Patrick for Ireland (17 Mar), St George for England (23 Apr) and St Andrew for Scotland (30 Nov). They were and are days for wearing something extra (like a daffodil if you're Welsh!) to signify allegiance. Maybe an extra pint down the pub would come in to it, but that's pretty much all.
What can I say, then, but God Bless America? You took our relatively quiet observance days and supersized them, even doubling Harvest (as far as the root intention behind it goes) with Thanksgiving, the one big knees up that hasn't crossed the pond and returned to us 'American style'.
You guys - you sure know how to party.