Robert Beith was born at the Fairfield Farm, Darlington, Durham County, Ontario in 1843. He was educated at Bowmanville and the Commercial College in Toronto. Working with his uncle, he was an ambitious and enterprising young farmer. With his brother James, they established the Waverley Stock Farm, Bowmanville in the 1880s. With a farming operation firmly established, they began importing Clydesdale horses, cattle and sheep from Scotland. Robert Beith and Co. started breeding Hackney horses with the purchase of five English mares and an imported stallion in Manitoba, in 1891. Breeding stock from other breeders were added to the farm as the operation expanded. His first imported stock arrived in 1892, continuing to bring to regular consignments to Canada until 1910. Wishing to promote the farm, they began to show at the biggest shows of the period. Competing at the 1893 Worlds Fair in Chicago, they exhibited three prize winners and two championships. Banquo, a homebred was judged Champion stallion at Chicago in 1897, and twice champion at Toronto. The death of Banquo was reported in the July 27, 1898 edition of the New York Times. Saxon, purchased from Rawlinson Bros., Calgary was judged Grand Champion Stallion at the 1904 St. Louis World Fair, and Priscilla, also bred by the Rawlinson Bros. was Champion Mare. Twice he had Champion stallion at National Horse Show, New York. Robin Adair II, purchased from the Rawlinson's was one New York Champion, and sold following his win for $6500. Waverley King, bred by Robert Beith and sold to Dr. Joseph Telfer, Milton, Ontario was Champion stallion at the Royal Winter Fair from 1922 until 1926. Breeding stock was sold across Canada, the United States and Argentina.

He was a founding member of the Canadian Hackney Society, He served as President from 1895 until 1899. He judged many of the leading shows in Canada and at the 1895 National Horse Show. He was commissioned in 1902 to buy and export horses for the British Military for use in the Boer War in South Africa.

In addition to his farm and importing, he was the Federal Member of Parliament for Durham West from 1891 until 1904. He was appointed to the Canadian Senate in 1907, continuing to serve until his death in January 1922. Senator Beith was Canada's first great promoter of the Hackney horse, he bought and sold throughout Canada and to U. S. breeders. He was proclaimed "The Hackney King of Canada" by the Toronto Globe newspaper.