This veteran character and his younger brother, western actor Jack Rockwell, were born to American parents south of the border in Vera Cruz, Mexico in 1882. Charles Trowbridge was educated in Napa, California and Hawaii, then studied for his degree at Stanford University. He forsook a thriving career as an architect in his twenties for stage acting, receiving early training at the Alcazar Theatre in San Francisco with Bert Lytell and Bessie Barriscale. He then moved to New York where he earned a number of regional roles in the Chicago, Boston and Philadelphia areas before making his Broadway bow with "The Marriage Game" in 1913. He proceeded to build up his resume impressively with the plays "Daddy Long Legs" in 1914 and when it was revived in 1918, "The Broken Wing (1920), "Craig's Wife (1925), "Ladies Leave" (1929) and "Dinner at Eight" (1933). He made a sampling of silents over the years as well, primarily in drama, with The Fight (1915), Thais (1917) and The Eternal Magdalene (1919) to name a few. After co-starring opposite Corinne Griffith in Island Wives (1922), however, he was not seen again for nearly a decade.

After a steady diet of Broadway plays, he was signed by Paramount for character roles in sound pictures and proceeded to support the top stars. With his rangy build, piercing blue eyes, premature gray hair and serious countenance, Trowbridge was particularly useful throughout the 1930s and 1940s in crime yarns, horrors and in rugged settings starting out with Gary Cooper and Carole Lombard in the romantic drama I Take This Woman (1931). Trowbridge usually adopted a friendly but intelligent, officious demeanor as assorted doctors, judges, bankers, lawyers, military brass and even U.S. presidents. He appeared rather indiscriminately in a number of "A" quality films including Captains Courageous (1937), Cihan Hakimi (1941), Aslan Yürekli Çavuş (1941) and Ömre bedel kadın (1945), and in popular cliffhangers such as King of the Texas Rangers (1941), Adventures of the Flying Cadets (1943) and Yüzbaşı Amerika (1944). He often played well-meaning victims who died in the first reel, notably in horrors. His last two films were unbilled bits, courtesy of John Ford, in Kader böyle istiyordu (1957) and Son Çığlık (1958). Retired thereafter, Trowbridge passed away a number of years later at age 85.