The POD for this map is in 1871, when Bismarck listens to his better instincts and instead ignores Moltke; Alsace-Lorraine is not annexed. Because of this, he is under greater pressure from the Prussian militarists to build a German Empire, which he and his successors do over the next thirty years.
The 1874 General Election results in a Hung Parliament; the IPP holds the balance of power and a few reforms are passed. The election is re-run in 1876 and, under the new leadership of Charles Parnell, the IPP demands Home Rule; Gladstone is suddenly 'converted' and pushes it through in 1876 with the help of a divided Conservative Party. Gladstone is re-elected by landslide in 1878 and governs for six more years. During this time he propounds his vision of 'Liberal Imperialism'. He sees the Empire as being about development and civilisation, and thus creates the 'Governed Colony' classification. A Governed Colony is one with limited autonomy and discretionary spending powers; the Governors have executive power with a view towards development. They are generally geared towards economic exploitation and are generally formed from areas with significant white landowning minorities, such as Kenya and Malaya.
The 1880s see crisis in the Balkans: Bulgaria under Prince Alexander and PM Stambolov pursue union with Eastern Rumelia. In response, Serbia invades in 1885 yet is defeated: Bulgaria annexes areas of Macedonia in revenge. The success of the campaign means that the liberals Prince and PM secure their hold on power (unlike OTL's 1886 coup) and over the next ten years move away from Russia towards Austria. The 1880s also see the Scramble for Africa reach its fullest peak: Germany trades Tangyanika and Togoland for land in southern Bechuanaland while driving through from Cameroon to the Congo Free State.
The 1890s are dominated in Britain by India. Famine strikes Hyderabad in 1891, killing millions. The woeful response of the Maharaja leads to revolt which consumes central India for years. The Conservative government passes legislation taking power from the Princely States and giving it to British colonial officers. Eventually in 1896 India is made a Governed Colony, with a Viceroy invested with executive power. This is seen as a victory for the Tories despite their use of a Liberal invention.
The 1890s see disaster strike Italy in Africa in 1896 when the Battle of Adowa cripples their forces in Ethiopia. Ethiopian soldiers push through Eritrea and Italian forces are pushed into the sea; Massawa is secured by the British but Eritrea is lost to Italy. The disaster leads to the Italian government collapsing and the King is assassinated; revolution is only narrowly avoided. Italy takes part in the coalition suppressing the Boxers and receives a concession in China as a paltry compensation. Germany, Britain and France take the lion's share; Anglo-German rivalry in Shanghai leads to the city being internationalised. Germany also buys the Philippine Islands from Spain (no Spanish-American War ITTL).
The first decade of the 20th century sees a second crisis strike the Balkans. Bulgaria declares its independence in 1906, leading to war with the Ottoman Empire, Serbia and Romania. Bulgaria defeats them all with Italian and Austrian subsidy, and Italy takes the opportunity to make a land grab in Libya and the Dodecanese Islands. Russia threatens to intervene (despite the Russo-Japanese War) yet is backed down by Austria and Germany. Bulgaria signs a victor's peace in 1907, seizing large chunks of land. Alexander is crowned Tsar and forms a 'Three Emperor's League' with Germany and Austria. Stambolov takes to calling himself the 'Balkan Bismarck', a epithet which scares some and amuses others. Russia forms the 'Eastern Bloc' with Romania and Serbia yet, despite their entreaties, is unable to get France to join in, at least formally. France is quite satisfied as it is, and doesn't want to goad the Germans once more.
Map in next post...