Nope, I was born too late for it to be a culture shock- and began 1st grade in fall of 1959!
Lessee: Dad bought a new 1959 Opel Rekord Caravan(station wagon) that was our family car for at least 5 years. I well remember gas station attendants walking around it, looking at it sideways, & asking,"Whut kinda car IS that?"
Dad's boss had one too- ours was blue, his was gray. So my involvement with foreign cars goes *Way* back.
A family in the next town had already started a decades long affair with Volkswagens. About the same time, my uncle from Californa got a VW camper van/microbus, & drove from CA to ETx in it with his wife & 4 sons!
Someone local had one of those little foreign amphibious cars- I remember watching it drive into the lake- & there were at least 2 Nash Metropolitans in town- though I'm unsure if the Nashes were made overseas or just looked like they were.
All the above were on the scene in a tiny East Texas town circa 1959-1961- but it's true that foreign cars were a tiny percentage of the local vehicles, surely no more than 1% or so, probably less.
It was the mid to late 1960's before the percentages had changed in a big way. By then, VW was the foreign car king. Toyota & Datsun(Nissan) finally showed up in our area, especially Datsuns with their little pickups & the original 240Z. But American brands were still the huge majority.
So- tiny minority way back then? Yes. Culture shock? No way!