Well, to make a long story short, Mark Rothko was Jewish!
Since Mark Rothko's mother was Jewish, and in Orthodox Judaism and Conservative Judaism, those with a Jewish mother (or those who underwent a halakhic conversion) are considered Jewish, then that makes him Jewish. His father was Jewish too.
Mark Rothko (whose full birth name was Markus Yakovlevich Rothkowitz) was born on September 25, 1903 in Daugavpils, Russian Empire (now Latvia). Mark Rothko passed away on February 25, 1970.
Rothko was an abstract painter, best known for his color field paintings that depicted irregular and painterly rectangular regions of color, which he produced from 1949 to 1970.
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