As far as the US goes it is Ricky Carmichael.
Nino Farina won the first ever World Championship race at Silverstone on 13th May 1950.
No history recorded on this.
Motocross Championship was created in 1994.
Motocross Championship happened in 1994.
He won the cruserweight championship first
Oregon ducks won the first National Championship in 1939.
They won their first championship against the Miami HEAT in the 2011 NBA championship.
If you want to know his first championship it was with Matt hardy on raw they won the WCW Tag Team Championship but his first major championship was at Armageddon he won against Edge and Triple H for The WWE Championship
Andre Agassi won his first professional tournament in Argentina at the age of 17. He won his first major championship at age 22, when he won Wimbledon in 1992.
fabulous moolah she is the first women has won the womens championship and she hold the title for 28 years
They won their first championship at Madison Square Garden in 1970.
Helms Championship 1933.