Jackie Stewart acquired his third title after a hard battle with Lotus and decided to quit while he was at the top. Once again the season was blighted, with the deaths of François Cevert and newcomer Roger Williamson.
Colin Chapman's fortunes certainly looked good. Fittipaldi and Peterson represented a Lotus team of two top drivers, but some people remembered the previous time the team tried that with Rindt and Hill in 1969 - and Stewart won the championship. Stewart and Cevert had developed into a fine partnership, and Hulme and Revson looked good at McLaren.
Ickx was joined at Ferrari by little Arturo Merzario, who had run a few races in 1972, while Regazzoni left to join Marlboro BRM. An intriguing new marque was the American-financed Shadow. The sinister black cars were handled by Jackie Oliver and George Follmer, an American veteran with no Formula One experience. Graham Hill quit Brabham to set up his own team.
Fittipaldi had a dream start to his title defence, winning in both Argentina and his native Brazil. The first was by no means easy, since Regazzoni and Cevert both led before having problems.
In South Africa McLaren introduced the sleek and very modern-looking M23, which would ultimately have a lifetime of six seasons. Hulme put it on pole, but fell to fifth as Stewart scored a fine win after a heavy practice crash. Mike Hailwood became a hero in the race as he rescued Regazzoni from his burning car.
Fittipaldi scored a third win in Spain, and then Stewart added a second in Belgium, where the track broke up and many cars skated off. Jackie won again in Monaco to make it three each for the main contenders. The race saw the debut of Briton James Hunt, in a March run by aristocrat Lord Hesketh.
For the first time Sweden hosted a race at the Anderstorp circuit and, although local hero Peterson was on pole, Hulme gave the M23 its maiden victory. Ronnie got his revenge in France, finally scoring his first win after suffering appalling luck in the early races. It did not help him much at Silverstone, where the race was stopped after a multi-car pile-up was triggered by Jody Scheckter. Revson won the restarted race after Stewart spun out.
Tragedy returned to Zandvoort, when Roger Williamson - in only his second race - was killed in a fiery crash. Stewart and Cevert scored a one-two, a feat they repeated in Germany. In Austria, Peterson waved Fittipaldi through, but won anyway when Emerson retired.
At Monza Peterson and Fittipaldi finished one-two, but the title went to Stewart. After an early stop he charged through the field to an amazing fourth place.
Revson won the chaotic, rain-hit Canadian race, which saw the first use of a pace car in Formula One. The circus moved to Watkins Glen where Stewart planned to have his 100th and last grand prix. But Cevert was killed in practice, and Tyrrell withdrew.
It was a bitter end to a fantastic farewell season for JYS. In the race Peterson picked up a fourth win, but he was pushed hard by the fast-improving Hunt.