John Raymond McNamara was born on December 3, 1917, in Long Island City, Queens, New York. His parents, John and Ida, were 28 and 34 years old, respectively, at the time of his birth. John was the youngest of three siblings, with two sisters named Catherine and Marion. The family initially lived at 283 Freeman Avenue, and John was Christened at St. Patrick Roman Catholic Church.

 

Before 1930, the McNamara family moved to their long-time residence at 20-64 41st Street in the Astoria section of Queens. This location was approximately one mile from North Beach Airport, later known as LaGuardia Airport. John developed a keen interest in aviation and regularly visited North Beach Airport to observe planes and follow aviators such as Charles Lindbergh. During the 1930s, he extensively photographed early aircraft.

​

Following his high school graduation, John attended Fordham University from 1935 to 1938. Unfortunately, due to family financial difficulties, he had to leave college. In 1938, John secured a position with Metropolitan Life, one of the world's largest insurance companies headquartered in New York City.