Answer by taking a quote from the following article:

Caesar was the youngest of three sons born to Jewish immigrants living in Yonkers, New York. His father was Max Ziser (1874-1946) and his mother was Ida (nee Raphael) (1887-1975). They likely were from Dabrowa Tarnowska, Poland. Reports state that the surname "Caesar" was given to Max, as a child, by an immigration official at Ellis Island.

Caesar's television career began with an appearance on Milton Berle's Texaco Star Theater in the fall of 1948. In early 1949, Caesar and Liebman met with Pat Weaver, vice president of television at NBC, which led to Caesar's first series, Admiral Broadway Revue with Imogene Coca. The Friday show was simultaneously broadcast on NBC and the DuMont network, and was an immediate success. However, its sponsor, Admiral, an appliance company, could not keep up with the demand for its new television sets, so the show was cancelled after 26 weeks--ironically, on account of its runaway success.  On February 25, 1950, Caesar appeared in the first episode of Your Show of Shows, initially the second half of the two-hour umbrella show, Saturday Night Review; at the end of the 1950-51 season, Your Show of Shows became its own, 90-minute program from the Interntional Theatre at 5 Columbus Circle and later The Center Theatre at Sixth Avenue and 49th Street.  Burgess Meredith hosted the first two shows, and the premiere featured musical guests Gertrude Lawrence, Lily Pons and Robert Merrill. The show was a mix of sketch comedy, movie and television satires, Caesar's monologues, musical guests, and large production numbers. Guests included: Jackie Cooper, Robert Preston, Rex Harrison, Eddie Albert, Michael Redgrave, Basil Rathbone, Charlton Heston, Geraldine Page, Douglas Fairbanks Jr., Pearl Bailey, Fred Allen, Benny Goodman, Lena Horne and many other stars of the time. It was also responsible for bringing together the comedy team of Caesar, Coca, Carl Reiner, and Howard Morris. Many writers also got their break creating the show's sketches, including Lucille Kallen, Mel Brooks, Neil Simon, Michael Stewart, Mel Tolkin and Sheldon Keller. Sid Caesar won his first Emmy in 1952. In 1951 and 1952, he was voted the United States' Best Comedian in Motion Picture Daily's TV poll. The show ended after almost 160 episodes on June 5, 1954.  A few months later, Caesar returned with Caesar's Hour, a one-hour sketch/variety show with Morris, Reiner, Bea Arthur and other members of his former crew. Nanette Fabray replaced Coca, who had left to star in her own short-lived series. Ultimate creative and technical control was now in Caesar's hands, originating from the Century Theater and the weekly budget doubled to $125,000. The premiere on September 27, 1954, featured Gina Lollobrigida. Everything was performed live, including the commercials.  Caesar's Hour was followed by ABC's short-lived Sid Caesar Invites You from January 26 to May 25, 1958. It briefly reunited Caesar, Coca, and Reiner, with Simon and Brooks among the writers.  In 1963, Caesar appeared on television, on stage, and in the movies. Several As Caesar Sees It specials evolved into the 1963-64 Sid Caesar Show (which alternated with Edie Adams in Here's Edie). He starred with Virginia Martin in the Broadway musical Little Me, with book by Simon, choreography by Bob Fosse, and music by Cy Coleman. Playing eight parts with 32 costume changes, he was nominated in 1963 for a Tony Award for Best Leading Actor in a Musical. On film, Caesar and Adams played a husband and wife drawn into a mad race to find buried loot in the 1963 comedy extravaganza It's a Mad, Mad, Mad, Mad World.

How did he get that spot?
1948. In early 1949, Caesar and Liebman met with Pat Weaver,