Wikipedia: Katz's Delicatessen
Katz's Delicatessen, also known as Katz's of New York City, is a kosher-style delicatessen located at 205 East Houston Street, on the southwest corner of Houston and Ludlow Streets on the Lower East Side in Manhattan, New York City.
During the peak of the Yiddish theater, the restaurant was frequently full of actors, singers and comedians from the many theaters on Second Avenue as well as the National Theater on Houston Street. During World War II, the two sons of the owners – Lenny Katz and Izzy Tarowsky – were both serving their country in the armed forces, and the family tradition of sending food to their sons became sealed as the company slogan "Send A Salami To Your Boy In The Army". The slogan was coined by Izzy's mother Rose Tarowsky, whose son served in the South Pacific as a bomber pilot.
12 November 1943, Washington (DC) Post, pg. 13:
The New Yorker will do a profile on Louie, the Waiter, who coined the couplet, "Send a Salami to Your Boy in the Army," and who alone sold $2,060,000 in war bonds at the delicatessen in the Fifties where he is employed.
10 December 1962, Wall Street Journal (New York, NY), pg. 17:
SEND A SALAMI
(Ad for Katz's Delicatessen - ed.)
7 April 1963, Los Angeles (CA) Times, pg. M9:
Opened in 1888, Katz also operates a mail order business, shipping salamis around the world. During World War II his slogan was: SEND A SALAMI TO YOUR BOY IN THE ARMY.
13 January 1972, New York (NY) Times, pg. 44:
Louis Schwartz, Waiter, Dies:
Sold $9-Million in War Bonds
"Send a Salami"
As "Louie the Waiter," working in the Sixth Avenue Delicatessen, between 55th and 56th Streets, Mr. Schwartz suited his tactics to his customers to persuade them to buy war bonds.
The bonds he sold paid for 66 P-47 Thunderbolt fighter planes and each bore the name "Louie the Waiter" and his sales record to that date.
Mr. Schwartz, a short, plump man with a bouncy walk and pink cheeks, was given to composing doggerel. His customers and his colleagues called him a poet, quoting one of his more famed creations, "Sent (sic) a Salami to Your Boy in the Army."
30 December 2001, New York (NY) Times, pg. CY11:
(212) 254-2246; 205 East Houston Street, (Ludlow Street); $; Article 1/1/99
While classic Jewish delis are dwindling in number in New York, Katz's has kept going since 1888. By the time Katz's hung its famous World Was II sign, "Send a Salami to Your Boy in the Army," the place was already an institution.
My great grandparents also owned a Deli in NYC, not far from Katz’s. Family legend has it that Louis stole the slogan from my great grandparents, who first coined the term.