So the original comment was removed which is annoying because I've just written this response and now have nowhere to put it. So I'm going to post it anyway because I feel like it. I hadn't even got to the end so apologies for what I've missed out. I'll write a proper answer to the question in a bit. Apologies OP if this seems slightly aggressive - its not aimed at you but whoever that other commentor was. Also damn you mods for being good at your jobs and removing bad posts

Although your basic outline is fundamentally right, you are really not being accurate in many of these statements. And also please stop using the word "tribes" as it is not an acceptable term for these ethnic groups or societies.

The Rhodesian war had blacks and whites on BOTH sides

Okay, semantically speaking there were a smattering of whites on the side of the nationalist forces. But only a tiny amount. Literally dozens. And of those only three ever really "fought" against the white state - Paul Brickhill, John Conradie, Peter Mackay. Some white missionaries located in rural areas also opposed the white state (such as Donal Lamont or Janice McLaughlin) and assisted the guerrillas where possible. However, just as many didn't. Criticisms of the nationalist forces were as forthcoming from the Catholic Church (for example) as they were of the Rhodesian security forces (see the publications of the Catholic Commission for Justice and Peace in Zimbabwe). It was fundamentally a racialist war of white against black, at least from the perspective of the African nationalists. The Rhodesian security forces were heavily dependent on African troops [for more see my post here on why African troops fought for the white state against their fellow Africans] but for ZANU and ZAPU it was still a war against the white population rather than any multi-racial forces. Those Africans who fought for the state were decried as traitors and "whores" [Mugabe, Our War of Liberation, p.65]

Great Britain wanting the majority of government to be black, but Ian Smith was not a fan of this because he believed it was difficult to implement a black government that was free from tribal-prejudice.

The war was fundamentally about the desires of the African majority to rule themselves, independent of Britain or the white settlers in Rhodesia. This was not Britain versus the Rhodesian Front. This was an internal struggle between white settlers and the African majority. (And FYI the term majority rule does not mean that the majority of the government should be African, it means that the majority of the population should choose the government.) Smith and the RF also firmly believed that majority rule couldn't work because they were not "civilised enough". This was the same view espoused by the Capricorn Africa Society or the white nationalists in South Africa. As the war progressed Smith also turned more and more to the threat of communism in order to make this war about a grander ideological battle than it was. The nationalists despised the British as much as they did the settlers.

This did not sit well with GB and the Shona people of Zimbabwe. So war occurred.

This did not sit well with anybody in the world except for South Africa and the Portuguese (because of their colonies in Angola and Mozambique). Hence the sanctions. The international context was crucial at this time. Between 1957 and 1965, a wave of decolonization spread across Africa, and the fact that the other two members of the Southern Rhodesian-led Central African Federation (Nyasaland/Malawi and Northern Rhodesia/Zambia) both struggled for independence in full view of their neighbour to the south inspired many to take up arms. Furthermore, it was not just the Shona who disagreed. The Ndebele also did (and FYI the Matabele and Ndebele are the same people....)

As historians have shown (namely Terence Ranger and Ngwabi Bhebe, and Norma Kriger) many Africans did not join the war effort because of UDI. Many joined because of their local grievances, specifically the uneven division of land and the incredibly repressive nature of the white state against any African political movements. The Land Apportionment Act was perhaps the most significant of the racially discriminatory laws, alongside the Land Husbandry Act (which saw cattle slaughtered indiscriminately to meet quotas) and the dreaded Law and Order (Maintenance) Act (which permitted detention without charge or trial). This was not some large scale ideological conflict - principally it was about basic human rights and the fact that a minority of the population earned ten times what Africans did, owned more than half the land despite being less than 5% of the population, and ruled the country with a heavily racialised franchise [see another of my posts on this subject here].

You had the Rhodesian Government (mainly supported by South Africa, and was aligned with various tribes) versus ZANLA and ZIPRA (now ZANU-FP, who were supported by Soviet Russia and Cuba and were mainly the Shona tribe)

Admittedly this is largely correct. ZANLA and ZIPRA though were the armed wings of ZANU and ZAPU respectively, the actual political parties and which had both begun as ZAPU in the mid -1960s. ZANU was backed by the USSR and Cuba, ZAPU by China. They also had the entire African continent apart from South Africa behind them, particularly the Frontline States (Zambia, Malawi, Angola, Mozambique, Botswana, Tanzania, and Lesotho) who provided them with financial assistance and equipment, and permitted them to set up camps on their territory near Rhodesia's borders in Mozambique and Zambia particularly.

The Rhodesian Government was not aligned with any tribes. Between 1966 (when the war began with the Battle of Sinoia) and 1977 the RF repeatedly sought the support of "chiefs" as a means of justifying their persistent refusal to relinquish power and claim they represented the "voice of all people in Rhodesia". This was not the case. The Pearce Commission proved this as did the failure of the Internal Settlement between Abel Muzorewa and Ian Smith in March 1978.

The Rhodesian Government was relatively successful, but faced serious sanctions from the UN etc. So they had to withdraw and accept defeat.

The Rhodesian Government was not relatively successful. By 1979 they had lost control of 85% of the country. For every Rhodesian soldier there were an estimated 4 African guerrillas in the country and a further twenty in the camps on the borders. This idea that Rhodesia was crippled by sanctions and could have won the war is a myth started by Ian Smith (see the "Great Betrayal") and propagated by Rhodies in internet forums ever since. The war could have dragged out for another few years with the Rhodesian security forces holding onto the primary urban areas but the countryside was effectively out of their control, particularly in areas like Umtali near to the borders.

So, what was their master plan? Keep the current government, which consisted of a majority of whites, but also had representation of Matabele (a black tribe) people. And then slowly transition to a black majority government.

No. Why are the Ndebele (not Matabele which is the old term for this group) being grouped in with the Rhodesian Front state? They were no more sympathetic to the state than the Shona were, or any of the multitude of other ethnic groups in Zimbabwe. In fact, Joshua Nkomo who lead ZAPU throughout the war and indeed had been a prominent nationalist since the founding of the Southern Rhodesian African National Congress in 1957 was Ndebele. ZAPU was primarily Ndebele. The war in Matabeleland was fought just as fiercely as in Mashonaland. Indeed the Ndebele and Shona fought each other as much as they did the Rhodesian state at times, because both wanted control of the nation after independence. The death of Herbert Chitepo by a car-bomb highlights this uncertainty.

The master plan of Ian Smith and the Rhodesian Front was, as you rightly say, gradual African advancement. Take selected elite Africans, civilise them, raise them to levels of Western acceptance and then slowly integrate them into positions of power over the course of 20 years. This was entirely unnacceptable to every nation in the world bar South Africa. Why should the indigenous majority population have no say over the running of their nation? Furthermore, Smith's various plans always tried to maintain a blocking minority of whites in Parliament, plus control over the economic sector and the military, plus the judicial system. (See the 1978 constitution for example). Again, this was completely unacceptable and entirely racialist in motivation. The examples of the Congo or Angola were repeatedly brought out as horrific examples of what happened when Africans seized power but the white Rhodesian state never highlighted Ghana or Tanzania or Botswana as successful examples. Fear was their overwhelming tool in the fight against African nationalism.

How did they expect to win with such a tiny proportion of the population onside? Well, it wasn't tiny. It had the Zimbabwean Zulu, the Matabele, the Ndebele and the Limpopo people (and the majority of white Zimbabweans).

No. Not true. First off, the Matabele and Ndebele are the same ethnic group. The Limpopo people and Zulu are both small ethnic groups in Zimbabwe and whilst it is entirely possible that some may have fought in the military of the Rhodesian state, it is untrue (according to David Lan in Guns and Rain) that the societies as a whole sided with the white state. Furthermore, it was a tiny proportion of the population.

[cont'd below]

Okay, OP, so now to answer your question. What was white Rhodesia's endgame during the Bush War? Fundamentally, it was to hold on long enough to ensure white jobs and security whilst a transitional government was put in place, eventually leading to majority rule over the course of fifteen or twenty years. Realistically, their objective changed dramatically over the course of the war.

In the early 1960s when violence began to emerge in the African townships, the white state sought to suppress any mass African movement by arresting and detaining the leaders, therefore hopefully leaving the ordinary African who "cared little for politics" as a docile population. Thousands were arrested each year. Hundreds were sent to Gonakudzingwa, the isolated restriction centre in rural Rhodesia - not under arrest they were only restricted to a certain area around the isolated camp. Any particularly troublesome Africans were placed in prison. What the newly elected Rhodesian Front government did hope for was a subservient African population whom they could spend the next fifteen or twenty years slowly bringing up to acceptable levels of "civilisation". Garfield Todd's multi-racial partnership ideals of the late 1950s were rejected as seeking to integrate Africans into positions of power too quickly - and Todd was at best a moderate liberal who supported advancement policies which would seem heavily racialist by contemporary standards. The election of the RF in 1963 was itself an indication of how race was becoming a "central modality through which people lived and experienced their lives" [Brian Raftopoulos, Becoming Zimbabwe, p.xxii). War was inevitable in such a society where unarmed blacks were gunned down simply for taking part in protests.

In 1966 when the first actual engagement between the nationalist guerrillas and the regime's security forces occurred, the white state was focused more on recovering from its declaration of independence in November of the year before, than on any insurgency within its borders. Today Zanu-PF heralds the Battle of Sinoia as the launching of its liberation war, but in reality serious, intense, and prolonged conflict was still a few years away. For now the Rhodesian state sought to build its economy (which it did successfully for the later half of the 1960s), attract new white immigrants (which it also did, reaching a peak in 1968), and build relationships with South Africa and the Portuguese colonies. By 1970 the government was firmly in control of the African population and the RF was firmly in control of the white population. The guerrillas had waged large scale, open, pitched battles which the state (with its air superiority and better weaponry and training) won decisively. Between 1966 and 1968 the Rhodesian security forces lost only 13 men, whilst killing 150 guerrillas and capturing 292 more. [Godwin and Hancock, Rhodesians Never Die, p.90]

This didn't last.

By 1972, the ZANU liberation forces had infiltrated the north-east of the country to a large extent and began employing hit and run tactics which the state struggled to counter initially. Isolated rural white farmers bore the brunt of the attacks. Operation Hurricane, the name given to the Security Forces attempts to reclaim the territory between 1972 and 1974 was eventually fairly successful but only short lived. The Lisbon Coup of April 1974 saw the formerly friendly Portuguese colony of Mozambique become an independent nation the following year and a strong hold for ZANLA. 764 miles of border opened up to guerrilla incursions and Smith became incredibly reliant on South Africa - 80% of Rhodesia's foreign trade came through its southern neighbour. South Africa realised Rhodesia's future was increasingly fragile and immediately changed Rhodesia's status to dispensable, seeking instead to build stronger ties with the other independent black states. South Africa could see white Rhodesia couldn't last when four of its five neighbours were hostile to the white minority rule, even if the Rhodesian Front couldn't see it themselves.

From this point onwards, Smith was constantly under pressure to settle with "moderate" Africans such as Abel Muzorewa, a well-liked and fairly popular Bishop who was the head of the African National Council. The white population was begin to fracture under the increasing pressure of both sanctions and the war. Conscription ages were widened which further angered the white population. The number of Africans joining the guerrilla forces was increasing. The re-introduction of rationing of fuel (the famous "petrol coupons"), the growing number of whites leaving the country, and the number of white civilians killed all increased the demands for settlement. From 1972 onwards, the end-game was to integrate some moderate Africans into the government and then use that multi-racial facade to persuade the guerrillas that racial segregation was over and there was no reason why they could not work with the whites. The war could be ended and everyone could go back to how it was before, except with a sheen of Africanism over the RF government.

The period of detente between 1974 and 1976 - when under pressure from South Africa's Prime Minister John Vorster, Rhodesia began negotiating with the nationalist forces - saw the objective of the state change again. Now Smith believed that by causing bitter infighting between the nationalist groups (ZANU under Ndabaningi Sithole, ZAPU under Joshua Nkomo and the ANC under Muzorewa), he could weaken their forces and unity and include only a weak element of them in a future government. Several prominent leaders were released, including Robert Mugabe, and a multitude of conferences were held between the various parties, including those of the Frontline States which supported the nationalists, in an attempt to find some compromise. It was at this time that Smith made his famous quote:

I do not believe in majority rule ever in Rhodesia, not in a thousand years. [20 March 1976]

He did not want majority rule, he wanted a white and black government where whites held the significant positions of power (military, judiciary, police, economy) for at least another decade. Obviously this was entirely unacceptable to ZANU and ZAPU, and as the Internal Settlement with Bishop Abel Muzorewa in March 1978 would show, could not bring an end to the war.

When peace was finally agreed upon at the Lancaster House conference in 1979, it was primarily a result of Smith's realisation that the white state just physically did not have enough people to continue. The international community's continued sanctions, the loss of South African support, the growing successes of African nationalist forces, and the pressure from Britain also conspired to destroy what will-power Smith had left to resist majority rule. He also believed that in 1979, any democratic elections would see Muzorewa and his United ANC remain in power, perhaps in a coalition with Joshua Nkomo, perceived as less radical than Robert Mugabe who had just taken control of ZANU. In such an event, Smith could likely retain some influence of power in the parliament. Guarantees were also made by the UK and the US to help with the reallocation of land, including providing funds to the Zimbabwean state to purchase such lands, which reassured white farmers that they would not be displaced. The policy of "willing seller, willing buyer" further provided assurances.

If you get a chance to read Ian Smith's book The Great Betrayal - do. It is perhaps the most useful insight into the mind of the man who almost single-handedly dragged Rhodesia into and then through the war, almost blind to the events occurring around him.

Hope this helps. Any questions please ask. If you want any specific sources to anything I've said, just ask. Two excellent books on this topic are Denis Hills, The Last Days of White Rhodesia and W.H. Morris-Jones, From Rhodesia to Zimbabwe.