Your map is in error. \
https://it.wikipedia.org/wiki/File:Africa_1885_map.png
The era start current is 1885, not 1914. The Germans are barely on the coasts and have not worked inland yet.
The Carolines, Gilberts and Marshalls are still Spanish, and the Bismarks are fiercely disputed with the British and the Dutch.
The US presence in Africa was LIBERIA. An 'independent' nation state. Sort of like British Egypt.
Confernce on the Congo.
Principle of Effective Occupation
The principle of effective occupation stated that powers could acquire rights over colonial lands only if they possessed them or had "effective occupation": in other words, if they had treaties with local leaders, if they flew their flag there, and if they established an administration in the territory to govern it with a police force to keep order. The colonial power could also make use of the colony economically. This principle became important not only as a basis for the European powers to acquire territorial sovereignty in Africa, but also for determining the limits of their respective overseas possessions, as effective occupation served in some instances as a criterion for settling disputes over the boundaries between colonies. But, as the Berlin Act was limited in its scope to the lands that fronted on the African coast, European powers in numerous instances later claimed rights over lands in the interior without demonstrating the requirement of effective occupation, as articulated in Article 35 of the Final Act.
At the Berlin Conference of 1885, the scope of the Principle of Effective Occupation was heavily contested between Germany and France. The Germans, who were new to the continent of Africa, believed that as far as the extension of power in Africa was concerned, no colonial power should have any legal right to a territory, unless the state exercised strong and effective political control. Since Germany was a latecomer to the continent and was unlikely to gain any possessions, it had an interest in embarrassing the other European powers on the continent and forcing them to give up their possessions if they could not muster a strong political presence. On the other side, the United Kingdom (UK) had large territorial "possessions" on the continent and wanted to keep them while minimising its responsibilities and administrative costs. In the end, the British view prevailed.
The disinclination to rule what the Europeans had "conquered" is apparent throughout the protocols of the Berlin Conference, but especially in "The Principle of Effective Occupation." The powers finally agreed that this could be established by a European power establishing some kind of base on the coast, from which it was free to expand into the interior. The Europeans did not believe that the rules of occupation demanded European hegemony on the ground. The Belgians originally wanted to include that "effective occupation" required provisions that "cause peace to be administered", but other powers had that amendment struck out of the final document.
This principle, along with others that were written at the Conference allowed the Europeans to "conquer" Africa while doing as little as possible to administer or control it. The Principle of Effective Occupation did not apply so much to the hinterlands of Africa at the time of the conference. This gave rise to "hinterland theory," which basically gave any colonial power with coastal territory the right to claim political influence over an indefinite amount of inland territory. Since Africa was irregularly shaped, this theory caused problems and was later rejected
From the American point of view at the time,
the African agreement reached in Berlin was as worthless as the paper it was written upon.
For in fact, when the Americans set about to establish their own colonial administration, they actually meant hegemony over the territories they ruled. Hence the Hawaiian annexation, the Philippine War, the Cuba occupation, Puerto Rico flat out conquered and the Canal Zone heavily occupied.
As for Germany's Pacific empire.
The area marked in yellow was purchased from Spain. for about 18 MRM in 1899.
What makes this all interesting is that the Germans were actually after the Philippines itself and hoped during the Spanish American War to either by negotiation, bluff or guile to convince the Spanish to turn the colony over or mayhaps if the Americans sought to 'liberate' the Philippines as they had Cuba, the Germans could swoop in and either make a deal with Aguinaldo and take over with him as puppet, or if the United States stayed put, "share the hegemony". That is Kaiser Wilhelm II sought to cut a deal with the McKinley Administration to split the archipelago in two. This chicanery went so far as an offer to swap a German coaling station cable base and anchorage in the Bismarks for Mindanao!
USN archives.
This attempt backfired on the Germans. Hitherto, the German American relations in the Pacific had been somewhat formal but cordial despite the fiasco at Samoa. Vice-Admiral von Diedrichs the German commanding the German East Asia fleet was discovered interfering with US operations (American viewpoint, although he claimed he was on a survey and assessment of the situation mission. In the middle of a shooting war?). He had originally trained as a midshipman on American warships when Prussia set about organizing her first naval academy and imported American naval officers to set it up. Von Diederichs took his midshipman's cruise during an American expedition to China and Korea and thus was uniquely favored and placed later in his career by experience to take command of the German East Asia station.
None of the stuff that went wrong at Manila Nay, which was his fault, should have happened at all. Admiral von Diederichs knew first hand that American naval customs and warfare was not conformable to "European" rules since the United States had not been a party to them and did not follow them.
He also was aware that George Dewey had a hair trigger temper for his other European (French) compeers had warned him. But I really don't blame von Diederichs. The man had just successfully bluffed the Chinese Qing government into yielding the Tsing Tsao (Dalian) anchorage under a similar set of Kaiser Wilhelm II orders. He might have thought the chaos in Manila and on Luzon allowed him the same gunboat diplomacy leverage to effect some kind of concessions on the harassed Americans or the Filipinos, both of whom he tried to game. I don't think Aguinaldo trusted Diederichs or the other Germans farther than he could see him or them, and as for Dewey, well being lectured by the flag secretary representative officer sent to him by an upstart foreign navy admiral was not going to sit well with an American admiral, especially a very tired short of sleep angry one in the middle of a shooting war who had just blasted one enemy fleet into ruin for just sitting there.
With Otto Bismark gone and tyros running the German foreign ministry the Kaiser was more or less doing as he wished in the field of foreign relations and so far his colonial ad hockery with his confused ill considered and often out of touch with reality personally issued orders to various German ambassadors, consuls and military officers had produced some decent results for Germany, even if it had ruffled French, Italian and British feathers hitherto.
But this was the United States, now, not some Chinese potentate or some rival European nation's colonial administration manned by cautious bureaucrats who were afraid of mistakes and consequences if they overreacted. Bluff and bargains made under duress of threat would not work with the U.S..
The upshot was that Dewey called in a USN marker from his sudden newfound British buddy Admiral Chichester, (courted at Hong Kong before Dewey sailed for Manila)also at Manila Bay with his fleet and Diederichs found himself staring into the first Anglo-American showdown. Bluff was met with a real threat and from that day forward, Germany was solidly slotted into the enemies column as far as the USN was concerned. Hard feelings cemented in place and were transmitted to Washington. One of the recipients of Dewey's accounts was Theodore Roosevelt. Not a good enemy to create was Theodore Roosevelt.
Still, it was a minor bone headed mistake Berlin made, but it would be American remembered and amplified later when the Zimmerman telegram was handed over (America's new friends the British supplied the contents.) after the Lusitania Incident. That telegram did for Germany what that less than competent Spanish ambassador Enrique Dupuy de Lome's letter which called McKinley a political hack did for Spain right after the Maine blew up.
And all that started because von Diederichs forgot the first rule of neutrals in a live fire war zone. STAY NEUTRAL and be cautious.