The son of Ned McCarr, a prominent trainer-driver from the mid-1890s until the late 1930s, Ken McCarr became one of the sport's leading historians. He was, for many years, a practicing horseman, grooming some top campaigners. He thereby came to be on a first name basis with many of the top drivers, trainers and owners. McCarr assumed the post of registrar for the USTA in 1948 and served in this capacity for 22 years. He was for a time the editor of The Horseman And Fair World magazine and wrote regularly for Hoof Beats and The Harness Horse. Ken McCarr died in 1977 in Columbus, Ohio.
Published in the Harness Racing Museum's 1994 book, The Immortals