Churchill and Roosevelt attended, as did de Gaulle and Giraud. (General Henri Giraud had replaced Admiral Darlan as Vichy French governor for Africa.) Stalin could not attend because of the pressing military situation in the Soviet Union.
Stalin had sent a message advocating the opening of a second front in Europe at the earliest opportunity. Roosevelt favoured a landing in France (although, at the time, he was very focused on the Pacific) and Churchill favoured a landing in Italy: “the soft underbelly of Europe.”
Roosevelt got his way with France, although the D-Day landing in Normandy had to wait until 1944. Churchill got his way much earlier with Italy, and Allied forces landed in Sicily (Operation Husky) in July 1943.
Two controversial decisions that came out of the Casablanca conference were the decision to intensify the bombing of Germany and to demand the ‘unconditional surrender’ of Germany, Italy, and Japan.