The Kinnock Premiership (1986-1994, won 1986, 1990)
The Kinnock Premiership is notable for overseeing the end of the Cold War at the close of the 1980s, and also for returning one of the younger Prime Ministers to work in the UK - seen as a turn away from aged politics with the defeated Tory leader Heath 70 years old.. Kinnock saw the reunification of Germany, with the former East Germany being subsumed in to (West) Germany, agreeing not to oppose it as long as Germany remained within the European Community and NATO, thereby precluding a military or economic conflict, whilst also seemingly being relaxed to the potential expansion of the European Community to eastern Europe. This was also Labour's first time to shine since the economic woes of the 1970s as Britain underwent a transformation.
With a large United Kingdom, spread across the globe, Kinnock appointed another Royal Commission on the future of the United Kingdom system. The Commission visited Canada and Australia in particular, both countries under a monarchy, operating a Westminster style of politics, and functioning as a federation, but also visited West Germany (as it was at the time) to study how German federalism functioned. The Commission looked at the division of powers, how the federation functioned, and the causes of tension - taking note in particular of Quebec in Canada which had a referendum on independence in 1980. It's report was noted by the Labour Government in 1992, and largely enacted soon after, laying out the principles of the division of powers between Westminster and the Home Nation assemblies. It also made substantial reference to the Canadian doctrine of "pith and substance", allowing for the House of Lords Judicial Committee to rule on the aims of a law and the de facto results of a law to judge which jurisdiction they should sit under.
Of more visible impact to much of the general population was the reform of the House of Lords, covered in part by the earlier Royal Commission. The existing hereditary heirs were to lose their right to sit in the House of Lords, with the numbers decreasing year-by-year, and they would be replaced by a set of appointed peers, with the same powers as the existing House of Lords (as it was to continue unelected). Each year, a set of people would be ennobled and allowed to sit in the House of Lords for 12 years, after which they could be re-appointed if so wished, with the allotment of places mostly decided on the suggestion of the UK Government - but with some places reserved for suggestion by the devolved administrations. For the first time, the devolved administrations would have a voice in Westminster legislation, the ability to influence, even if the numbers in the House of Lords and power of the chamber were limited (*1).
Being a committed unionist as well as Labour Prime Minister, changes showed up elsewhere. The rollout of universal healthcare to the overseas regions was complete, but work to link up the systems with a globally unique patient identifier was needed in order to allow patients to move and transfer around the system. The Royal Mail expanded it's coverage to fully UK-wide, with postal codes allocated to the various islands. Telecommunications were modernised with "British Telecommunications" being split off from the Post Office organisation, and investing in a new core fibre-optic network which would stretch across Great Britain and Northern Ireland, also linking to Gibraltar and Malta in order to provide core services. A British-French joint venture was formed to collaboratively do the same across the Atlantic, linking the UK & France to Guadeloupe and Barbados - a further West Indies network would then link Barbados to the other islands. This was utilised by the BBC, and thereafter the other terrestrial radio & television networks to broadcast equally in Great Britain, Northern Ireland and all overseas regions; this also meant the TV license was expanded to those regions too, although it was to be incrementally increased from a half of the standard GB price to equal with GB price over 15 years. This also saw the standardisation of all parts of the UK under the British telecoms system and within the +44 international dialling code, although designed in such a way that calls in the America to the British Caribbean would avoid being routed back and forth across the Atlantic, and would therefore see most of the West Indies moving away from the unified North American Numbering Plan for the British Numbering Plan (*2) - "integration means integration" as one minister put it.
As such, Kinnock's Premiership - in hindsight - is looked upon as the period of time where the UK overseas region became socially and culturally integrated in to the UK, instead of just legally (and partially economically). Emerging technologies allowed better simultaneous experiences across the entire United Kingdom, with the BBC expanding it's remit, whilst the Wisden Trophy took on a new meaning. The Wisden Trophy, a cricket trophy between England (technically and Wales) and the West Indies islands, now became largely a domestic "bragging rights" match - although several non-UK players from other islands such as Jamaica still competed for the West Indies. The "Protected Sports Coverage" list was passed in to law by Kinnock's government, providing a list of events which had to be shown on TV - events being categorised firstly as either "full free-to-air coverage" or "free-to-air highlights coverage", and then whether the event was "UK-wide" or just in the "Home Nation". Events such as the football, cricket and rugby World Cups, Five Nations, Summer & Winter Olympics, Commonwealth Games Wimbledon (tennis) all gained full coverage on a UK-wide scale, giving the entire nation unifying shared moments.
Kinnock would also expand the United Kingdom again - just a little bit - bowing to significant pressure from the Falklands in particular for integration. The South Atlantic Act of Union would see the Falkland Islands, South Georgia & South Sandwich Islands, St Helena, Ascension and Tristan da Cunha all integrate as a "South Atlantic" Home Nation within the United Kingdom, some having defined themselves as "more British then Britain" in the past. This was much to Argentine displeasure - but having been defeated in war and undergoing their own political turmoil, there was little to be done about it bar protest at the United Nations and make clear their unrelinquished claim to "Las Malvinas". The North Atlantic Act of Union saw the British Virgin Islands and Turks & Caicos Islands integrated within the West Indies. This brought the total to nine Home Nations within the United Kingdom (England, Wales, Scotland, Northern Ireland, Malta, Gibraltar, Seychelles, West Indies and South Atlantic). There were consequences to this expansion though, as in 1991 Kinnock closed down much of the remaining Singapore Royal Navy base, bring an end to just over 50 years of HMS Sembawang, with a new UK-Singapore agreement providing for defence responsibilities in collaboration with Australia, and also rendering support services if and when needed by the Royal Navy (as well as certain other Commonwealth partner navies) for repair, refuel & resupply. This decision, brought significant debate within the House of Commons, as "reducing Britain's global influence and power", but justified by the Government on economic measures, and the lack of need for UK strategy for a base in Singapore.
Looking overseas, with Guatemala seemingly tacitly accepting the existence of British Honduras, the nation gained independence as "Belize" in 1991, as did Brunei at the same time. The Trucial States also ended their protectorate status, gaining independence, as the United Arab Emirates, Qatar and Bahrain, given the less irredentist Saudi Arabia to their south as they engaged in a new "Great Game" between the Arab powers. Kinnock tried to draw the UK, Jordan, Oman and the former Trucial States in to a new military alliance, but was rebuffed, retaining only really close relations with Jordan and Oman - something pounced upon by his Parliamentary opposition. Kinnock was quickly entangled by military action overseas though; not normally a forte of Labour governments. Significant action in the Gulf War in 1990, backing up the United States in liberating Kuwait - a former British protectorate - bought Kinnock allies in the US, something which would allow Britain to play a larger role in working with Jordan to negotiate a lasting peace agreement with Israel, a key regional US ally (*3). Further action in collaboration with the East Africans saw intervention in the Rwandan Civil War, once news of an ongoing genocide leaked out, with British air power deployed via the Seychelles at Assumption Island base. The British played an important, but largely supporting role with East Africa leading in restoring law and order in Rwanda and then Burundi; the two nations were later amalgamated again as "Buranda" and acceded to the East African Federation as state, popularly supported as the least worst way of preventing one ethnic group gaining supremacy over the other in Rwanda & Burundu, as well as bringing a chance at some economic recovery.
By the early 1990s, the situation in Northern Ireland had improved substantially enough for face to face negotiations to restart over the future of Northern Ireland. Although at times peaceful - helped in no end by the British Army's decision to frequently use troops from other areas of the United Kingdom to avoid English troops enflaming tensions (especially Maltese given their frequent dual nature as both British and Catholic) - not infrequent spurts of violence between paramilitary factions flared up. Kinnock's 7 years in power saw an agreement brokered by his government, with the most paramilitaries agreeing to a ceasire, and both Kinnock and the Irish Republic's Prime Minister declaring that the future of Northern Ireland must be decided by those in Northern Ireland through peaceful and democratic means. Further talks, including the various factions in Northern Ireland directly, tackled difficult issues involving weapon decomissioning, marches and policing, but eventually an agreement (the "Belfast Accords") was achieved, allowing the restoration of devolved governance in Northern Ireland after ratification by a referendum in 1993. The creation of the new Northern Irish Assembly would be modelled on the existing devolution pattern in the United Kingdom, and the presence of both the Irish Republic and Northern Ireland within both the European Union Customs Union and the Common Travel Area would allow virtually all border checks to be removed, to be replaced by specific intelligence-led searches.
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(*1) I'd imagine something along the lines of 45 Lords being appointed per year or so (with a 12 year mandate, so 540 Lords, plus a few Lords Spiritual), with some appointed by the PM, and some appointed by the First Minister of the devolved governments?
(*2) Along with the telecoms reforms at the time, I'd imagine 01xx area codes being "Great Britain" geographic phone numbers and 02xx being "Northern Ireland & Overseas Regions".
(*3) Having not embarrassed itself in the Middle East with the Suez Crisis, Britain is a more trusted partner in the area, even if people know that British military power is rapidly fading.
Late PS: I can't decide whether the UK adding Emancipation Day is overdoing it or not. It's really a rebranding of the existing OTL pre-1971 early August bank holiday, which ties in nicely with existing celebrations in the West Indies, so it's not really an "additional" holiday. I see it being presented publicly as "let's celebrate the UK emancipating the slaves" and just quietly overlook what happened previously to that.