(Please note that this article is about the composer of the ragtime piece The Sponge. There was a composer named Walter Cleveland Simon during this same time frame, but he was associated with the Melville Clark piano company, and specialized in composing themes for silent films, playing organ accompaniments for same, then later arranging for electric organs. A note on his work can be found in a excerpt from Film Music: A History, by James Wierzbicki, on Google Books.)

Walter C. Simon was born in New Orleans, Louisiana, to Gustave Martin "Gus" Simon and his wife Ella Scanlon. While some later sources put his birth year at 1886, the 1900 census and New Orleans birth records clearly show it as 1885. He had two younger siblings, including Anita (7/1887) and Ivo Adolph (10/5/1890), both born in Tennessee. The 1900 census showed the family living in New Orleans, with Gus working as a correspondent clerk. Anita died at some point over the subsequent decade. According to his daughter Sally, Walter had little or no formal music training but was considered a child prodigy, traveling throughout the South at age eleven and up giving classical concerts, including one at New York's famed Carnegie Hall. That he was versed in this music suggests that he actually did have at least some early musical training, but mostly picked up tunes by rote. At age 16 he started to appear in New Orleans city directories as a music teacher, working out of his parent's home.

Around 1903 or so, Gus and Walter became employees of the Louis Grunewald Music Company, a chain that had a large presence in New Orleans. They even had their own line of pianos which were built by Bradbury Piano Company (later part of the Winter Piano Company). The company was also an early champion of player pianos and pushup players. The 1910 census take in New Orleans showed father and son respectively as the manager of the music store and a professional pianist working there. As for Simon's ability as a performer by this time, that aspect is unclear and not readily found in New Orleans papers. A roller skating accident in his late teens or early twenties injured one of his hands and effectively ended his concertizing career. However, he was ambitious as a salesperson, as noted in this Music Trade Review mention in their November 4, 1911, issue:

Simon initially self-published what appears to be his only piano rag composition. Copyrighted in August of 1910, The Sponge: Two Step hit the streets with a 1911 copyright shown in the footer, and was distributed by Grunewald. At the very least, The Sponge is eclectic and unusual, and certainly unpolished in its structure, with a bevy of moving fifths in the second section to complicate things. The final repeat of the opening theme is in a 15-bar section instead of the usual 16 bars. While the title seems innocuous enough, supported by the cover, it very likely referred to the British term "sponge," which described either a pimp or a male prostitute, and which had somehow made it into the lingo of the American South in the 1850s. There were also a couple of songs copyrighted by Walter from Detroit, Michigan, where he also lived for a time in the late 1940s. This includes a re-copyright of The Sponge from Detroit in 1912.

Walter continued to work for his father, who managed the Grunewald store, through the mid-1910s. Around 1917, he took some interest in learning how to fly. The following year while World War I was escalating in England and France and the Americans joined in the fight, he went over to England to train as a pilot with the Royal Flying Corps, predecessor of the Royal Air Force. Having started in March, by June he was flying patrols with the 139th Squadron under William Barker, working in Bristol Fighters. On the morning of July 30, 1918, while patrolling the Italian Front, Walter, with the help of his observer, shot down five German fighters in one flight, thus becoming the first American "one-day" ace of the war, and actually in Army Air Corp history. He flew successful missions until nearly the end of the conflict, and became a training pilot as well. Walter received the Distinguished Flying Cross from the British Government for his effort. The official DFC citation, published November 2, 1918, read:

From 1919 until the late 1920s, Walter was engaged by the Peruvian government to train their pilots in Bristols, then later airplane models, in essence helping to form the Peruvian Air Force. The January, 1920 census showed him on one of his breaks, residing with his family in New Orleans, with his father and brother still managing the Grunewald piano store. A passport from March indicated that he was not only training pilots, but selling the "aeroplanes" as well to Lima, Peru, perhaps even to private enterprises. During his time there Simon was promoted to the rank of First Lieutenant and was the Vice-Director of the Naval Flying School at Ancon. The school was run by another RFC pilot, Captain Juan Swayne Leguia, who was also the son of the Peruvian president at that time. Walter made several journeys down to South America, with his last verifiable trip in 1928. However, as he was not found in the 1930 Federal census, he may have still been out of the United States at that time. During his time in Peru Walter was married to a woman named Louisa, and she bore him a daughter named Mary Phyllis around 1925. They were separated by the early 1930s.

In 1933, Walter married Dorothy Ann Brabb in West Virginia. Over the next seven years they would have four children, including Ann (1933), Thomas H. (1934), Nancy (1939) and Sally (1940). The 1935 Florida and 1940 Federal censuses showed the Simon family residing in Hollywood, Florida, just outside of Fort Lauderdale, with Walter working as a stockbroker in both records. When he filled out his draft record in 1942, taking eleven years off his actual age (perhaps to assure his participation in the war), the family was living in Manhattan, New York, on Madison Avenue, with Walter employed on Wall Street. In 1943 the family relocated to Detroit, Michigan.

Walter, given the rank of Corporal, managed to fly a few missions with the Army Air Corp in World War II, but was utilized for his fighter pilot training skills as well. After that the family briefly relocated to Topeka, Kansas, where Walter worked in the Army Air Force Reserve Training Program. They later returned to Detroit, where the family was found for the 1950 census, with Walter working as a "customer's man" for a brokerage. Dorothy Ann died in 1953. Walter subsequently was married to Helen Corruthers of Cincinnati, Ohio, and divided his time between Detroit and Manhattan as he finished out his career as a broker well into the late 1950s. It is uncertain as to why, but it appears that sometime during the 1950s, Walter changed the spelling of his last name to Simone, which is reflected on at least two passenger lists and a change in his Social Security record, originated in Florida. His daughter Sally was not sure what the motivation for the change was, but noted that he rarely talked about his past or career, and suspected that he kept quite a bit of his life secret from others. As Walter Carl Simone he died in 1971 in Kingsport, Tennessee, at age 85.