In 1964, recognizing his uncompromising patriotism, his devotion to work, and his more than forty-five years of service painting naval subjects, Beau was awarded the Navy’s most prestigious civilian award, the Navy Meritorious Public Service Citation.
Beau wrote this note to the Secretary of the Navy, the Honorable Paul H. Nitze, thanking him.
"Please accept my sincere and heartfelt thanks for this great honor, which I treasure above all other commendations. The work accomplished over the years in painting and recording for history the activities of the Navy I love so well, I feel has been a great privilege and a distinct pleasure."
In 1964, Beau also began painting a new series of images featuring the earliest sailing ships of the fledgling Navy. This project was to occupy his attention for more than ten years. This historic series of warships from the Revolutionary War period and the War of 1812 contain some of his finest work, reminiscent of the early ship portraits he executed first in the early 1930s on the occasion of the USS Constitution visits to ports in California. Similar to his contemporary, the famed British artist, Montague Dawson, a master painter of great sailing vessels, Beaumont depicted maritime scenes in watercolor, of the USS Constellation and the USS Constitution et al. In1976, the Navy employed these historic images as part of the publicity campaign organized for the National Bicentennial Celebration.
Beau continued his work for the Navy throughout his final years. In 1966, at the age of 76, he traveled secretly to Vietnam to record the Navy's small craft operations against the Viet Cong on the Mekong River. His Navy travels began to slow after Vietnam. Instead, he traveled extensively with Dot, his wife, Together for the first time, they visited Navy friends and acquaintances throughout the world. Beau never did officially retire, but the necessities of age did require him to slow down. A persistent backlog of commissions kept him painting in his studio throughout his later years. On the stairwell of his Laguna Hills studio/home, a woven banner from an English pub was proudly displayed with the words "Take Courage". This banner gave Beau the inspiration to climb the stairs each day and paint in his studio, well into his late eighties.
His last major commission came from the National Steel Company in San Diego. He was retained to paint each ship in a new class of amphibious vessels, twenty-four separate ships in all. He completed these twenty-four paintings between 1970 and 1973.
And in 1976, two years before he passed away, Beau was honored with his final major retrospective exhibition at one of his favorite venues, the Laguna Beach Museum of Art. Over his career, he had exhibited in Laguna on more occasions than in any other venue. The retrospective filled the entire museum and contained 127 works chronicling the years 1916 to 1976. It was very well received, and set attendance records at the museum at the time. An excerpt from the museum brochure reads "Today, as we honor this Artist Laureate of the Fleet. Mr. Beaumont continues to research with acute perception and produce with unwavering quality historically significant commissions."
On January 23, 1978, Beau passed away at his home in Laguna Hills, California. He was survived by his wife, four children, thirteen grandchildren, and eight great-grandchildren.
On learning of Beau's death, his longtime friend, Admiral Arleigh Burke, former Chief of Naval Operations, wrote to Dot: "Great talent is given to but few men and Beau gained the respect and admiration of his peers by his great paintings. But he also gained even more ardent admiration from those of us who were not expert in his difficult field, but who, as sailors realized that Beau put the spirit of the sea into his paintings as it is felt and cannot be expressed by those who go down to the sea in ships. Beau loved the sea and his work showed it. He loved the Navy as few men do, and Navy people in generations to come will be grateful to him for his inspiring paintings....He was beloved for his personal characteristics... He was a man of great integrity coupled with unusual understanding. He was a great man. He will be sorely missed."