The 73rd Hunger Games.Effie mentioned that both tributes from District 12 ate like savages and had no sense of etiquette or manners. This angered Katniss, as both were from the Seam and therefore they had never had a decent meal in their lives. Katniss mentions that Caesar's hair and make-up color was crimson and appeared to be bleeding.
In the film, Ceaser Flickerman and Claudius Templesmith watch a rerun of these games. Ceaser comments that's the ruined city arena was one of his "favorites." These games were supposedly won by a dark-skinned tribute, who in the film Katniss watched is seen killing Titus.
So this means that the victor of the 73rd Hunger Games was the male tribute from District 11, who killed Titus to win the Hunger Games.
This was Seneca Crane's second year as Head Gamemaker.