So…. after the Inquisition. Jews Were Tested With Pork Sandwiches
Jews who stayed in Christian countries after 1492, passed for goyem by taking goyische names, going to Mass and crossing themselves whenever possible.
Eating ham became a test since many of these perfidious yiddem would 
avoid the tasty Christian meat.
So then, so now. Poor David Milibank is running to become Britain’s first Yid PM! The last person of Jewish descent to try this, Disraeli, was a fervent, Yorkshire ham-eating Episcopal convert (as was Marx).