Seven drivers were leading the Formula One World Drivers' Championship at the end of the last Grand Prix they contested, (includes those who retired as series champion, but not active drivers). Who are they?
Alain Prost?, only one I can think of
Mike Hawthorne, (1958),
Jackie Stewart, (1973), and
Alain Prost, (1993), retired as World Champions. Hawthorne died in a road accident several months later.
Wolfgang von Tripps was leading the World Championship in 1961, when he was killed in a collision with Jim Clark on lap 2 of the Italian Grand Prix. von Tripps' team mate at Ferrari, Phil Hill, won the race, and became World Champion.
Jim Clark won the opening race of the 1968 season in South Africa, but died in a Formula Two race before the start of the European season. Clark's Lotus team mate Graham Hill won that year's championship.
Jochen Rindt was killed in practice for the 1970 Italian Grand Prix, and became F1's only postumous World Champion, as no other driver was able to surpass his 45 points from five race wins.
Didier Pironi was leading the 1982 World Championship when he crashed heavily in wet conditions during a practice session at the German Grand Prix, after having won pole position for the race in qualifying. Pironi never drove in F1 again, and died in 1987 in an offshore power boating race. Keke Rosberg scored enough points in the five remaining races to become World Champ.