Buck was born to Malcolm L. Marsh Sr. and Louise Bell Marsh in Florence, Alabama, on May 16, 1923. Malcolm Sr. was a concrete engineer building dams for TVA within the Tennessee Valley region. Buck and his two younger brothers grew up playing baseball and hunting the woods of the Tennessee Valley as their family moved from one project to the next.

While attending Tennessee Tech University, Buck was drafted into the US Army in 1943 and served as an infantry rifleman in the 36th Armored Infantry Regiment, 3rd Armored Division, in World War 2. Buck entered combat with this “Spearhead” unit in Belgium in December 1944, just as they engaged the German Wehrmacht’s massive counterattack, known as the Battle of the Bulge. The battle raged without ceasing from December 16, 1944, to January 25, 1945.

US forces suffered 19,000 KIA and 70,300 wounded or MIA. After repelling the Germans, the 3rd Armored Division “Spearhead” advanced through Cologne, Germany, and liberated the Nordhausen Concentration Camp. After serving eight months in the Occupation Forces, Buck sailed for home on the troop transport USS Wakefield in January 1946. He was discharged as a First Sergeant at Ft. McPherson, Georgia; his Eisenhower jacket was adorned with three combat infantry badges and a Purple Heart. Buck lived the rest of his life in honor and memory of the eighty-eight Rifle Company A men killed in action.

After returning home, Buck met Wanda Mitchell on the tennis courts in Florence; they both attended Auburn and married in 1949. They began raising a family in Florence until they moved to Auburn in 1970, where he joined BKW Construction as a project superintendent.

Buck served on the advisory committee at St. Dunstan’s Episcopal Church for many years and oversaw an extensive renovation to the church’s gothic revival structure in 1988, the construction of a garden close in 2012, and a columbarium in 2015. Throughout his life, he remained a trusted adviser to his friends on the vestry.

Buck served his college fraternity, Phi Delta Theta, as a house corporation board member for over forty years and sixteen years as president. He made lifelong friendships with generations of Phis, from the men of his class of 1949 to young men who had only recently graduated.

Buck self-published his military service memoirs, Reflections of a WWII Infantryman, in 2011 and is prominently featured in the non-fiction book Spearhead, a 2019 New York Times best-selling account by Adam Makos of a 3rd Armored Division tank commander and the battle for Cologne.

In 2017, Buck was honored as the Gameday Hero at the Auburn vs. Georgia football game.

In 2019, Buck attended the 75th Anniversary Commemoration of the Battle of the Bulge in Bastogne, Belgium. He dined with Secretary of Defense Mark Esper and King Phillipe of Belgium and made a short speech honoring the service and sacrifice of US forces. A snippet of his speech was broadcast on most national news channels that very evening.