next year, there will be 3 world championship driver in the Grand Prix, but which season have most world championship driver at the season? How much?

just recalling from my head, in 1986 there was 4 - piquet, prost, rosberg, alan jones, plus two "future" champions - senna and mansell.

1999 was 3 or 4 i think? schumacher, hill, villeneuve, and hakkinen ??

1998 also had 4, if you include Mika Hakkinen who was World Champion that year...

Best I can think of just now.

1970 Italian GP.

Jack Brabham
Denny Hulme
Jackie Stewart
John Surtees
Graham Hill
Jochen Rindt (he died during the weekend and became posthumous world champion later)

Emerson Fittpaldi was also here, he would become world champion later.

If we count only champions from earlier years then at the beginning of 1968 season (Kyalami race) there were also 5 champions:
Jack Brabham
Graham Hill
Jim Clark
John Surtees
Denny Hulme

If we're counting world champions yet to be, 1979 had eight.

Mario Andretti
Niki Lauda
Nelson Piquet
Jody Scheckter
Emerson Fittipaldi
James Hunt
Keke Rosberg
Alan Jones

So all in all this milleniums seasons have been pretty poor and lacking high quality competitition by comparison

well as people are including future champions, (and to make gezmoor feel better) 2003 would have 4 champions. schumacher, raikonnnen, alonso, villeneuve.
or 5 in 2001.

Quote from gezmoor :

So all in all this milleniums seasons have been pretty poor and lacking high quality competitition by comparison

Let's be fair. Schumacher won 5 (I think) consecutive WDCs prior to 2005, and then he retired at the end of 2007. So that means aside from Alonso, we've lost 5 years when a driver potentially could have become champion and continued to race to the present day.

There are at least three potential near-future WDCs in the current ranks, so don't put down your bets just yet. Ten years from now you could look back to this day and count 8 WDCs.

Quote from gezmoor :

So all in all this milleniums seasons have been pretty poor and lacking high quality competitition by comparison

Well because Schuey dominated F1 in this decade, we arent gonna get loads of World champ's

If we included Bou (world championshp of CCWS), we also have 4 WC driver in 2009 :P

Quote from pacesetter :

Well because Schuey dominated F1 in this decade, we arent gonna get loads of World champ's

Exactly my point. Much as I admire Schuey's talent, he kinda made F1 boring with regards to who was going to be the next WDC.