In the mid-1800s, the term coach dog emerged after Dalmations demonstrated an affinity for horses and for accompanying horse-drawn carriages. Coachmen would depend on the dog to keep the horses calm and to guard their rigs when they were away. The breed also played this role with fire apparatus, earning the nickname "Firehouse Dog.” The Dalmatian was well suited for this job, with his natural endurance and guarding instincts. To this day, the Dalmation Club of America road trails showcase the breed’s coaching abilities.
References:
American Kennel Club. (2017). 22nd Edition of The New Complete Dog Book : official breed standards and profiles for over 200 breeds.Mount Joy, PA: Fox Chapel Publishing.