He was a pioneer of professional race-riding, developing a trademark late finishing style, known as the 'Chifney rush' and was the retained jockey of the Prince of Wales.

He became the leading horseman of his day, winning four runnings of the Oaks and one of the Derby, but his career ended in ignominy after a scandal around a ride on the Prince of Wales's horse, Escape.

Chifney was born in Northwold, Norfolk around 1753[2] and, entering Foxe's stables at Newmarket Racecourse in 1770, soon learned the rudiments of horse racing.

[4] He was also known to be something of a dandy, to an extent that bordered on the effeminate, with hair flowing out from the front of his cap, ruffs and frills on his clothing and bunches of ribbons on his boots.

[5] This self-confidence and attitude distinguished him as "the first professional jockey as we understand the term",[4] although added to this, he had a reputation for dishonesty – "he dressed like a mannequin, nurtured an ego the size of a house and was as bent as a paper clip.

[10] On Eagle, an idle horse that he advised the Duke of Dorset to buy from Sir Frank Standish, he ran in the King's Plate at Newmarket.

[10] Another favoured tactic of Chifney's was easing the load on a horse's back by constantly adjusting his seat throughout a race.

[8] Chifney's manner of riding has been described thus: "He approached a race as if it were a piece of music, playing it slow and quiet until coming at the end with a beautifully modulated crescendo, sweeping past his one-paced rivals.

[1] On 14 July 1790 Chifney was hired as "rider for life" by the Prince of Wales to ride his racehorses at a salary of 200 guineas a year.

On Thursday 20 October, Chifney rode the Prince's horse, Escape, at Newmarket in a 60 guinea race over two miles of the Ditch in Course.

[12][5] Suspicions were immediately raised that Chifney had pulled the horse in the original race to secure a better price for his money on the Friday.

He stated that the horse had needed the race on the Thursday to "clear his pipes" and, knowing this, he had had no bet on the first run and 20 guineas on the second.

[5] In consequence, not wanting to make an example of his jockey, the Prince of Wales sold his stable and ended his connection with the turf.

[14][15] Warwick Lake was known to dislike Chifney's influence and arrogance and may, according to Jockey Club member Anthony St Leger, have been the driving force behind the case.

In 1800, he published The Narrative or Address of Samuel Chifney, Rider for Life to his Royal Highness the Prince of Wales at a price of two shillings sixpence.

The year before, he was again castigated for his riding of Mr. Cookson's Sir Harry, but it afterwards became apparent that in this case the horse and not the rider was at fault.

On 31 May 1803 he publicly thrashed Lieutenant-Colonel George Leigh (an equerry to the Prince of Wales) for accusing his father of cheating during the Escape case.