Bernard Nenner was born in Manhattan, New York City, New York, USA, on 4 May 1907, to Austrian parents. He grew up in Chicago. At the beginning of World War I, his father bought a dairy and cattle farm and moved the family to Wisconsin. At the age of 10, he rode his horse to round up cows for milking and moved cattle from one pasture to another. After the war, his father, whose leg was badly broken by a kick from a horse, moved his family to Freeport, Long Island. It was there that Bernie spent one year in high school before starting work at a dry cleaner. At the age of 15, he started working as a delivery boy for A&P in New York. He quickly climbed the ranks, becoming a manager at the age of 20.

On 4 March 1928, at the age of 20, he married an 18-year-old Sophie. At the age of 21, he became a father for the first time when his wife gave birth to their son, Ronald. Several years afterward, they had a daughter, Lisa. He served on an aircraft carrier during World War II, traveling across the globe.

Throughout his life, he held various occupations, ranging from managing a chain of dry cleaner stores and engaging in photography to dealing with wastepaper. His dry-cleaning business expanded to 15 stores on the South Shore of Long Island, but he eventually sold the chain and relocated to Florida in 1950, settling in Pompano Beach. Eventually, he ventured into the establishment of mobile home parks in Florida. During a tornado in 1965, he was trapped inside one of the trailer offices with two other people, and the next thing he knew, he was up in the air, floating. When recounting this event, he jokingly added, “It was a nice feeling.” He sold his mobile home park business in 1974 and completely retired at the age of 67.

His wife passed away in 1993, after 63 years of marriage. He met a woman named Frances, remarried in 2003 and was widowed once again a decade later. In 2008, when Longlife Steel Buildings asked him if he would represent a company that manufactured an extremely durable workshop steel building designed to last a lifetime, he agreed. Subsequently, he filmed his first TV commercial at the age of 101. On his 104th birthday, he donated a $100,000 ambulance to emergency responders in Israel. At the age of 104, he had perfect hearing, corrected 20/20 vision, and walked unassisted.

When asked about the secret of his longevity, he attributed it to consuming very little meat, never smoking, exercising regularly, adding, “The rest is luck and the man upstairs.” At the age of 110, he ran a library at the Aston Gardens at Parkland Commons senior community where he lived and made sure to stay updated on the news. At the time, he had four grandchildren, and five great-grandchildren.

Nenner passed away in Parkland, Florida, USA, on 13 November 2017, at the age of 110 years, 193 days.