I do have data, but in Italian.
In the decade 1961-1970 Italian migration to Switzerland increased, because Switzerland needed more and more workers, in 1964 the two countries signed a new agreement about immigration policies and in 1970 there were over a million Italians in Switzerland.
Italian came mainly from Lombardy, Piedimont and north east (an area called tri-veneto) but in the middle 60s thanks to the economic boom in Italy they had the option of staying home so Switzerland started looking for workers in the southern regions.
You can read about it (in Italian) here
https://www.larivista.ch/laccordo-del-1964-relativo-allemigr...
> Most of them were Swiss for several hundred years before Italy was a country
Italy existed before it was an official country
Swiss occupied Italian cities in the 1500s
> don't think Ticinesi see themselves as any more Italian than the other population groups.
Just like in Veneto they see themselves differently from Italian from the south
It doesn't make them different though...
> . Or France and Belgium. Or the Netherlands and Belgium.
In fact they aren't immigrants
They are both EU citizens
The point is Ticino and northern Italy close to the border (Varese and Como area) are practically the same place
In Switzerland they speak Italian, French and German, in Italy we speak Italian and French and German are two recognized official languages, in some areas there are two official languages, documents can be written in both and places have double names for example Bolzano/Bozen or Noasca/Nauchi
There is even a franco-provençal recognized community in Apulia, in the deep south. Those countries go back in history for thousands of years, they had relations from the dawn of times, saying that an Italian or a French in Switzerland is an immigrant is like swearing in a church.
That's why we made EU, because especially the original group of 12 should have no reason to call people from other countries "immigrant"