Dennis Bartholomew McCarthy was born in Chicago, Illinois on September 18, 1893, according to his World War I draft card. However, the Social Security Death Index said his birth year was 1892, and the 2011 exhibition catalogue, Southeast Texas Art: Cross-Currents and Influences 1925–1965, said he was born in San Francisco, California.
In the 1900 U.S. Federal Census, he was the oldest of four children born to Barth and Nellie, Irish emigrants. They lived in Denver, Colorado at 2449 West 28 Avenue. According to the census, McCarthy was born September 1881 in Illinois. His father was a laborer.
Ten years later, the McCarthys remained in Denver. He was the oldest of nine children and was employed as a machinist. The date of his move to Chicago, Illinois is not known. He signed his World War I draft card on June 5, 1917. He resided at 507 North Lawler Avenue and was a cartoonist at the Chicago Herald. His description was medium height and build with blue eyes and black hair. During his service he was in San Antonio, Texas, the location of the aviation site Kelly Field. The book Kelly Field in the Great World War (1919) said:
The Kelly Field Eagle [newspaper] was fortunate in having as members of its staff men who were specialists in their line. Sgt. Dennis B. McCarthy, a cartoonist who had long been well-known in newspaper circles, immediately began to develop a series of what might be termed "punch" cartoons, with the result that his work was soon copied extensively….
In the 1920 census, McCarthy was married and lived in New Orleans, Louisiana at 2026 St. Charles Avenue. He was a newspaper cartoonist. Southeast Texas Art said, "…McCarthy worked for 15 years at the Hearst Enterprises in San Francisco and New York. Before 1925, McCarthy was a cartoonist for the Fort Worth Record. In the 1930s and 1940s, he worked for the [Texas newspapers] Beaumont Enterprise and Beaumont Journal as a cartoonist and journalist, illustrating his own articles on topics of historical, biographical, and political interest…."
McCarthy has not been found in the 1930 census. Editor & Publisher mentioned his strip for the San Francisco News. During World War II he contributed work to North American publications, an aircraft company. Flying Magazine, August 1944, noted the popularity of McCarthy's aviation industry creation: " 'Willie Wingflap,' an impish cartoon character, is drawn by a North American artist, Dennis McCarthy, and has proved so popular that the cartoons are being collected in book form for immediate publication….
After the war Southeast Texas Art said, "…A specialist in watercolor, he taught classes and provided lectures for many years at the Beaumont Art League. McCarthy also exhibited frequently at the Beaumont Art Museum…" Some of his watercolors can be viewed at the online catalogue on pages 65 through 67; at the bottom, enter a page number or click on the arrows or click the bottom corner of the page.
According to the Social Security Death Index, McCarthy lived in Las Vegas, Nevada. He passed away on May 22, 1973 in Prescott, Arizona, and was buried at the Prescott National Cemetery, according to U.S. Veterans Gravesites at Ancestry.com.