Sammy converted.
Those are the are two ways that Jews evaluate whether someone is Jewish. The rest of us who are not bound by rabinical rules on this often use the same criteria we use for every other ethnic group: if either parent is Jewish you are considered 1/2 Jewish.
Granted that wouldn't really cover the Sammy Davis Jr. case, but those are vanishingly rare.
Do you think someone can be 1/2 Christian?
Car accident and conversion to Judaism
Davis nearly died in an automobile accident on November 19, 1954 in San Bernardino, California, as he was making a return trip from Las Vegas to Los Angeles.[15] The accident occurred at a fork in U.S. Highway 66 at Cajon Boulevard and Kendall Drive. Davis lost his left eye as a result; he wore an eye patch for at least six months following the accident.[16][17] He appeared on What’s My Line wearing the patch.[18] Later, he was fitted for a glass eye, which he wore for the rest of his life.
While in the hospital, Davis’ friend, performer Eddie Cantor, told him about the similarities between the Jewish and black cultures. Prompted by this conversation, Davis — who was born to a Catholic mother and Protestant father — began studying the history of Jews. He converted to Judaism several years later.[1] One passage from his readings (from the book A History of The Jews by Abram L. Sachar), describing the endurance of the Jewish people, intrigued him in particular: “The Jews would not die. Three millennia of prophetic teaching had given them an unwavering spirit of resignation and had created in them a will to live which no disaster could crush”.[19] In many ways, the accident marked a turning point in Davis’ career, taking him from a well-known entertainer to a national celebrity and icon.[15]
Sammy converted.
“if either parent is Jewish you are considered 1/2 Jewish.”
Ah, the “Jewish according to Hitler” test.