Thomas Dugdale was the son of Captain James Lionel Dugdale of Crathorne Hall near Yarm in Yorkshire. He was educated at Eton College and Sandhurst. He joined the Army in 1916, serving with the Scots Greys in World War I and the Yorkshire Hussars in World War II. Dugdale married Nancy, daughter of Sir Charles Tennant, 1st Baronet, and Marguerite (née Miles) in 1936. He died in March 1977, aged 79. By then a peer, his son, James succeeded him as Baron Crathorne.