I have'nt gotten around to most fo the rest of the world outside of Southern Africa, but what I have so far;
The premise is that what became the Orange Free State IOTL followed a different path, forming the Republic of Oranje in the early 19th century,
early on it annexed Transvaal and absorbed the Zulu state soon after.
In the late early 1830's Oranje had managed to build up a relatively strong army and a small, but effective navy, helped in part do to the policies
that the government had established, promoting both population growth and 'immigration from anywhere but the Empire'.
The Republic of Natalia, which had itself suffered a population decrease do to Oranje's prosperity and immigration policy soon came under attack
by a rogue Zulu army that had refused to accept becoming part of Oranje.
While the Natalians successfully defeated the Zulu army they lost two dozen people out of a local population of 350, many of whom were the
strongest farmers and best trained in military matters.
The British, looking to expand British South Africa used the advantage to their degree and tried to annex Natal, however the population,
now majority Afrikaans refused the envoy for annexation, leading to the chief of the colony ordering troops to occupy and forcefully annex Natal.
This lead to Natal requesting help from it's larger neighbor Oranje, a request Oranje accepted.
The Oranjian army, thanks to the government having invested in the beginnings of a thorough transportation system, quickly made its way
into Natal and some parts of British South Africa.
The British, who had no issues with Oranje and currently busy with the Belgian Revolution and a war on the sub-continent had not stationed
a large force in South Africa, this allowed the Oranjian Army to take control of several areas relatively quickly and win several naval battles
with the small, inferior British navy stationed their at the time.
Once word spread back to London of the situation they quickly dispatched troops and a naval escort.
In the end the British, who had'nt sanctioned the action, agreed to cease any potential claims to Natal and gave up some of the territory
captured by Oranje as a show of good faith, however relations between the two would remain strained.
In the late 1840's Portugal, facing a financial crisis was approached by the Oranjian government, in return for claims to parts of Southern
Angola and small part of Southern-most Mozambique the Oranjians would pay them a handsome sum and offered to help them control the
colonies, after much debate and a rebellion in Northern Mozambique Portugal accepted.
In the 1850's the Crimean War raged and the sub-continent was something of a headache as the British faced a low-level insurgency in
newly annexed territories.
In Southern Africa however things were quiet, Orange had grown to become a very prosperous state, having large swaths of agricultural
and mineral wealth plus the benefits of a recent phase of industrialization.
However this peace would not last, as Herald Goodchild, the Colonial Governor of Southern Africa and son of Jacob Goodchild, the former
Colonial Governor who'd attacked Natal, began to want revenge.
Herald was not exactly the most stable or logical person in the best of times, and his fathers recent death and the differences between
Oranje and South Africa in prosperity took him over the edge as he, like his father before him ordered troops into another country without
consent from London.
This would prove a phenomenal mistake as the Oranjian army, larger in size and superiorly armed swept into South Africa, climaxing with
the ORS Erasmus, a proto-Ironclad along with a significant naval force sailed into the bay of Capetown and decimated the naval units
parked their.
Britain, now fighting Russia in Europe and native rebels on the sub-continent was not able to send any sizable force for nearly three months,
allowing the Oranjian military to take control of the South African colony.
Having faced a significant defeat in South Africa and still fighting elsewhere a year later the Treaty of Lisbon was signed ceding the colony,
with the exception of a part of Capetown, to Oranje on the condition that all British who wanted to could remain and that Britain would be
allowed to continue using the ports for the next century.
Over time Oranje expanded Northward, incorporating new territory into itself, while also unofficially making it very unpleasant for new colonies
in Southern Africa that were'nt either Portuguese or Dutch.