Samuel Etoo of Cameroon has not yet played for Cameroon in a world cup, as Cameroon have not yet qualified for it when he was in Barcelona.
Samuel Eto'o played for Cameroon in the 2014 FIFA World Cup.
I do not think Samuel etoo played in a world cup as Cameroon failed to qualify in the past two world cups.
Yes, Cameroon played in the FIFA world cup before. In Italia 1990, they reached the quarter-finals, the furthest an African nation had reached ever before.
Loïc Feudjou had played 2 times for Cameroon before the 2014 FIFA World Cup.
Nicolas N'Koulou had played 48 times for Cameroon before the 2014 FIFA World Cup.
Cédric Djeugoué had played 3 times for Cameroon before the 2014 FIFA World Cup.
Dany Nounkeu had played 16 times for Cameroon before the 2014 FIFA World Cup.
Alex Song had played 47 times for Cameroon before the 2014 FIFA World Cup.
Landry N'Guémo had played 40 times for Cameroon before the 2014 FIFA World Cup.
Vincent Aboubakar had played 24 times for Cameroon before the 2014 FIFA World Cup.
Jean Makoun had played 66 times for Cameroon before the 2014 FIFA World Cup.