Not nosey at all.
My mother was born in Germany. She met my English father just after the war and as you may imagine at that time the marriage caused many upsets - 'marrying the enemy'.
Although I am proud of my heritage and certainly my mother was never afraid to admit her heritage, we did have to avoid those 'Reminiscence days' when they did things like celebrating the Brits winning the war or singing songs they sang during the war years etc. as other dementia sufferers didn't always view 'the enemy' with such 'kind eyes' . Actually that was one blessing when she lost the ability to interact quite early on and by the time she was ready for the NH it was no longer a problem with any residents.
And proud of your heritage you should be - I am a genealogist by trade, so I empathise with these things. My Dad's family are Irish, and I am very Irish in my ways - Mum disliked the Irish, and when asked would say " I married your father, not the rest of them" - meaning all his 8 siblings!! I use my maiden name, as Grandad told us we had to be 'proud of who you are' bless him. The Irish have been ostracised all over the world.
So, in your Mother's case, the dementia has treated her kindly for the life she has now......