Nowadays, handicapping – that is, allocating each horse in a race weight according to its ability, such that every horse has an equal chance of winning – is performed by a team of dedicated, professional handicappers employed by the British Horseracing Authority (BHA).
However, prior to 1851, no compensation was made for horses of different abilities or different ages racing against each other. The man who effectively invented handicapping was Admiral Henry John Rous, who was elected a member of the Jockey Club in 1821, at the tender age of 26, and appointed senior steward of the Jockey Club in 1838, following his retirement from the Navy two years earlier.
In 1850, Rous published ‘The Laws and Practices of Horse Racing’ and the following year devised the first ‘weight-for-age’ scale. The weight-for-age scale, which is still in use today, describes weight allowances that younger horses receive from older rivals, over different distances at different times of year. By compensating for the lack of physical maturity in younger horses, the weight-for-age scale affords horses of different ages an equal chance of winning. Rous was renowned as an expert handicapper, especially in two-horse races, or ‘matches’, and was appointed official handicapper in 1855.