Well, to make a long story short, Harold Ramis was Jewish!
Since Harold Ramis'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.
Harold Ramis (whose full birth name was Harold Allen Ramis) was born on November 21, 1944 in Chicago, Illinois, U.S.. Harold Ramis passed away on February 24, 2014 (aged 69).
Harold Ramis was an American actor, director, writer, and comedian. His best-known film acting roles were as Egon Spengler in Ghostbusters (1984) and Ghostbusters II (1989) and Russell Ziskey in Stripes (1981); As a writer-director, his films include the comedies Caddyshack (1980), National Lampoon's Vacation (1983), Groundhog Day (1993), and Analyze This (1999). He was one of three screenwriters of the film National Lampoon's Animal House (1978).
If you see any details that require update, please Let us know!