Thanks to Project Zeno, Rome was recovering so well in fact that there were increasing population and resource pressures (including demand for slaves) to expand. The development of quinine from Cinchona bark back in 1837(1085) had greatly decreased fatalities from tropical diseases; allowing for deep penetrations into central Africa from long standing coastal outposts. However, especially in the case of the Congo: long supply trains, hazardous terrain, poor logistics, insufficient stocks of medicine, and native ambushes eventually put off the private entrepreneurs from conquering Africa's heart while making any offers of official attempts unpopular.
When Ulterior Australis was revealed to have numerous resource-rich islands, and later a massive island-continent, expeditions by Rome quickly moved into the area, shifting focus away from Africa in particular. This was a reaction to the sudden opening up of the large (considered empty) land mass so close to Nihhon, and Rome tried to head them off whenever possible. There was no real adventurous search for the 'great southern continent', it was seen only as a competition to claim all of the unsettled world.
After the 1930's(1177+) African natives started becoming increasingly difficult to deal with because of the influence of Samouri Torr's tactics. While the natives became ever better armed and organised, some sections of the Kushite Legions still lacked breechloaders. Thanks to the fears of standards falling behind Nihhon's and the potential bad propaganda, the Magastratus Arma was allotted the resources required to reorganise the quartermasters to increase the uniformity of the Legions, including the increase of private factory contracts.
It has been widely accepted that had the Menguren Empire's rise ended the era. Had the Menguren not risen and forced both Rome and Nihhon to guard their borders, Likely all of Africa would have been under Roman control within twenty more years, but that a World war would have occurred far sooner, perhaps as early as 1966(1213).