[2] Chassagne's long career spans the early road races as a riding mechanic on Darracq, Clément-Bayard and Hispano-Suiza automobiles, before he joined Sunbeam (later to become S.T.D.

Meticulous, resilient, calm with a delicate driving touch and mechanical sympathy[2] ‘Chass’[4] was held with the utmost regard and affection by his friends and colleagues, the finest engineers and drivers of their time; surely a testimony to his amiable, loyal and easy nature.

[5] On 26–27 June 1906 the first French Grand Prix de l'ACF was held in Le Mans; Rene Hanriot driving a Darracq was joined by his longtime friend Chassagne as a riding mechanic but had to retire due to engine trouble.

During this period, Chassagne was also working at Clément-Bayard, Senat workshops for airships and race-car engines on the development, assembly and testing of the experimental Demoiselles Santons-Dumont monoplanes.

Development, assembly and testing of the first Hanriot Monoplanes, Reims followed and in August 1910 Chassagne received his pilot licence certificate no.

[6] He subsequently participated in various events including the Baie de Seine estuary crossing; winning the Liege altitude & speed prizes.

It is at Hispano Suiza that Chassagne was acquainted with Works drivers Pilleverdier and Zucarelli the latter becoming with Georges Boillot, Jules Goux & Ernest Henry the Peugeot ‘Les Charlatans’[3] who revolutionized racing with the twin cam over head, four valve per cylinder engine design.

Motorboat racing in Monaco was a convenient test bed for engine technology and in 1913 Coatalen and Chassagne in a Sunbeam powered boat took part in the event.

Later that year at the Coupe de l'Auto at Boulogne Chassagne, with his riding mechanic A P Mitchell, retired on the seventh lap when lying third with a rear axle failure.

On 2 October 1913 at Brooklands Chassagne alternating in two-hour spells with Dario Resta and K. Lee Guinness of the eponymous Stout dynasty, set up a series of long distance World Records with a Sunbeam Grand Prix fitted with a Single- Seater body.

Two days later again at Brooklands, Chassagne with the Sunbeam Toodles V, won an event against Percy E. Lambert's Land Speed Record holder Talbot.

[8] Back in Brooklands in the larger 4.9 L Ballot and with riding mechanic Robert Laly[4] who was to become a lifelong friend, Chassagne made the fastest BARC lap of the year and finished second in the three handicap races.

In 22 June after 5:24:50hr in what he famously described as "a nightmare in sea of mud" Chassagne won the first postwar Tourist Trophy and the last motorcar Tourist Trophy to be run on the Isle of Man with Sunbeam III[14] a 1921 Sunbeam Grand Prix straight eight 3-litre modified for the event; Chassagne ordinarily a measured and meticulous driver was fazed by the atrocious weather conditions on the island that day but it remained "one of the greatest victories of his career".

with the invincible 1921 1.5 L Talbot Darracqs, in effect a half sized engine of Chassagne's winning Tourist Trophy car, but none gained him success.

Pre Great War Henry, together with 'Les Charlatans' was responsible for the development of the game changing Peugeot race engines with double overhead cam and four valve per cylinder.

Wolverhampton Experimental Department, ultimately testing the prototype car in Brooklands and helping to develop the Sunbeam Grand Prix team entry.

Talbot Darracq 1.5 L voiturette, Jean Chassagne had good success in 1925 obtaining fastest time of the day at the Gometz le Chatel Hillclimb and second fastest at the famous Gaillon Hillclimb but he ran out of fuel on the last lap in the Touring Car Grand Prix, Montlhéry which was run on distance, ballast & fuel formula.

By the time Chassagne joined the ranks of the 'Bentley boys' (age 47), Bentley's reputation in endurance racing was unequalled and his successes in Le Mans legendary.

That Chassagne was not 'past it' was made abundantly clear in the first Le Mans he took part in for Bentley sharing a car with another racing legend Henry Tim Birkin.

The fifth overall achieved whilst no doubt respectable tells little of the heroic performance Chassagne exhibited in this race, which to a very large extent exemplify the man.

Dorothy Paget to initiate the construction of a team of Blower Bentleys designed by Amherst Villiers and built at the Birkin's Works, Welwyn Garden City.

[21] At the 1930 Brooklands Double Twelve Chassagne shared Birkin's favourite Blower Bentley but the Mechan's frame broke and the car retired at 4.30 pm of the first day's racing.

[22] The Bentley Works Team was retired but the Birkin Blowers were entered in the 1930 Phoenix Park Irish Grand Prix where they had a close race with the Mercedes 7 litre supercharged; Chassagne car suffered from a lubrication problem.

After the Nazi occupation of France in 1939 Chassagne moved from his Paris home Maison Lafitte back to La Croisille -sur-Briance, Limoges[17] his birthplace.