English people were small at the time of the Boer wars too, there were problems finding enough suitable soldiers, the food rationing in WWII actually improved diet for the average worker.
Actually the Boer war brings to mind the fact that the Afrikaaner people of South Africa are noted for being of large stature.
They are primarily of Dutch origin as well but have long been separated from Holland. So the fact that these two societies would share the attribute of being tall suggests to me that Dutch tallness compared to everyone else is genetic in origin
Afrikaner here. I'm 6 feet tall and I'm the "short" one in my family and friend circle.
I'm an Iowan from USA. My 6' son is the shortest male in our entire extended family. German ancestors.
If it's not too personal, is your wife of German extraction too?
She's Italian and 5'3"
Three sons - 6', 6'3" and 6'4"
Sounds like your line is secure for another few generations at least!
My eldest has married a 6'1" Amazon. So yeah.
Do you know anyone in your community who don't have enough to eat but yet they are tall?
The poor ones tend to be tall but are skinny.
You can still see this phenomenon. People from disadvantaged backgrounds in European cities (for example inner city communities) tend to be smaller than average.