It was popular among the German New Yorkers, and may have been either invented or popularized in the Yorkville section of Manhattan in the early 1900s.
(Oxford English Dictionary)
Chiefly N. Amer.
[a. G. spritzer a splash.]
A mixture of wine and soda water; a drink of this mixture.
1961 in WEBSTER. 1964 Vogue Apr. 71/1 Drink Spritzer (dry white wine and soda). 1972 G. BAXT Burning Sappho iii. 50 Flo's [drink] was a white wine spritzer.
13 February 1938, New York Times, "Notes and Reflections on the Night Clubs" by Jack Gould, pg. 156:
ADVENTUROUS souls who mourn the demise of the speakeasy and the crafty devices which often distinguished its existence might refresh their memories by a visit to the cellar and second-floor joints up Yorkville way. Operating without benefit of liquor license and justifying a restaurant license by employing nimble-footed individuals who scurry to neighboring delicatessen or coffee put to fill an order, these places, of which there are about thirty in the area bounded by First and Third Avenues and Seventy-ninth and Ninetieth Streets, retain much of the flavor of yesterday's peephole establishments. They are not to be confused, naturally, with Yorkville's numerous legitimate places.
The advertised drink is a "spritzer," consisting of apple cider and seltzer, which retails for 15 or 25 cents a drink and wholesales at about 2 cents a drink.
26 December 1939, Tavern Weekly News, Patrick Murphy bartender column, pg. 8, cols. 1-4:
(Wine & Soda, Hock & Soda, and Spritzer -- ed.)
10 August 1943, New York Times, pg. 4 ad:
One of the most delightful of summer drinks is "spritzer" -- half well-chilled white wine, two cubes of ice, and sodas to fill. Essential, however, to full enjoyment of this beverage is the type and quality of the wine in it. Inglenook Traminer and Riesling have been carefully selected by us as having true Rhine wine quality as nearly as is approximated in America. Excellent for "spritzer", Inglenook Traminer, Riesling and Navalie White are also heartily recommended by us as medium-dry white table wines especially useful in summer, and which are agreeably moderate in price.
Bellows & Company, New York.
25 June 1950, New York Times, "Food" by Jane Nickerson, pg. 154:
FINALLY come the spritzer and all the other long drinks to be made with wine. Rhine wine and sparkling water, or, instead of verice, give the first.
27 May 1956, New York Times, pg. 217:
Knowing a long drink may give the illusion of two, dieters may decide on a spritzer -- chilled wine and soda water.
10 January 1959, Chicago Defender, pg. 16:
On the drinking side, remember that most cocktails run-over with calories. Dry red or white wine, mixed with soda water as a "spritzer" will last a long sipping time without supplying too many calories.
("New York" is the dateline of this story -- ed.)