Short answers, pulled from the story.
The North African campaign began on the 11th of June 1940 when British forces launched raids against Italian positions in Libya. This action followed Italy's declaration of war on France and the United Kingdom just one day earlier.
Erwin Rommel commanded the German Afrika Korps that arrived in Tripoli in February 1941. Hitler ordered this relatively small expeditionary force to reinforce the Italians and block Allied attempts to drive them out.
Allied landings began on the 8th of November 1942 and finished on the 16th of November in Vichy-held French North Africa. Generals Mark Clark and Dwight Eisenhower compelled Admiral François Darlan to order cessation of armed resistance on the 10th and the 11th of November.
Axis forces surrendered on the 13th of May 1943 yielding over 275,000 prisoners of war. This huge loss greatly reduced the military capacity of the Axis powers.
Ultra intercepts provided valuable information about times and routes of Axis supply shipments across the Mediterranean. It is estimated that 40% to 60% of Axis supply shipping was located and destroyed due to decrypted information.