1870-1880 : Rise to power !Now, a lot of things happened to Japan during this time period and I think it would be difficult to recount it all in chronological order especially since I lost several of the backup saves I used to keep for that period ( That's also why I can' provide any 1870 screenshots ! ). I'll rather give you a summary of the main events separated into different categories ( Economy, colonial expansion, Etc...).
Economy :
Economic growth continued smoothly in Japan for a few years with many technological advances that increased productivity of many industries ( And Japan started to get prestige out of its level 2 factories ). However, with the advent of new agricultural techniques (Steam Tractors) demand for coal suddenly soared worldwide and led to the first shortages and a global coal crisis for which the empire was ill prepared !
The coal mining sector had been quite neglected these past few years since the ressource was easily available on the world market. Besides, Japan did not have too many coal sites and most of them were already being exploited when the crisis struck !
Despite many trade agreements with coal producing countries, and agreeing to pay a premium price, coal was still extremely difficult to acquire and soon factories where shutting by lack of supplies.
The only way out would be heavy investments abroad (esp in the US but also in France and Colombia ) which was extremely expensive although as early as 1871 money, both state funds and private capital, had ceased to be a concern for the Japanese empire.

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Here is the coal production situation in 1875. In white you can see the coal mines being built. Many industries like steel and military gear productions have been shut down to help !
While the situation eased a little by 1876, it took the whole decade to completely solve the problem especially as level 3 factories started to replace older ones and the country started to build more and more steam powered ships and developped its railway further.
Here is the coal situation in 1880 :

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By the end of the period Japan owned 36 coal mines out of which 24 in the USA !!
There were other shortages of goods throughout the period ( Mechanical parts, wood , chemicals ...) but all of these were much easier to manage.
Manufactured goods also ceased to be an economic bottleneck by the end of the same period thanks to heavy investments and technological progress in that domain.
Once the coal crisis was over, Japanese industry soared to an unprecedented level bringing huge amount of prestige to the empire ! Japan PP increased from about 17000 PP in 1875 to over 47000 PP in 1880 and was second in rank just behind GB !!

- PP gain 1880.png (1.44 MiB) Viewed 10748 times
Trade and diplomacy :During the whole period, Japan continued to expand its commercial fleets with more and better ships in order to support both its trade and rapid colonial expansion. Soon japanese merchant fleets were active in every seas around the world and japan finally overtook the british becoming the world n°1 commercial power !
Japanese merchants were buying and reselling huge amounts of goods worldwide and the Japanese population had access to many diverse foreign wares in large quantities far superior to their own needs !
All this was helped by a very active diplomatic corp who was able to sign numerous deals and trade agreements worldwide.
However, the diplomatic focus changed somehow around 1875 : lots of efforts were made to secure the friendship of the USA and bring them to sign a defensive alliance with Japan ( needed to secure those coal mines !) and then it became also much more important for the admiralty to secure passage and supply rigths to allow recoaling of fleets worldwide as japan was becoming more and more entangled with the world at large.
By the end of the period such treaties signed with the USA, Chile, Argentina, Brazil, France, Siam, Columbia and a few other minors allowed the japanese navy to sail as far as Europe or West Africa without much problem. Only tricky part to navigate was the Indian ocean and the southern part of Africa but this was remediated by colonial expansion in that area.
Colonial expansion :After the initial push in the Pacific and the claiming of Northern Borneo ( which did not please the Dutch at all ), Japanese admiralty came to the conclusion that it was a matter of national security that the empire gained the ability to recoal and ressuply ships, protect shipping lanes and securel all the maritime approaches to the mainland by taking control of strategicaly placed and well protected anchorages along an arc going from the solomons Islands and the coral sea to the Malayan peninsula in south east Asia.
Forays were made in Papua/New Guinea and Rabaul by Japanese exploratory parties while missionaries and traders activity increased in Borneo and Johore to the dismay of the Dutch !
Most of Papua/New Guinea would join the empire in 1876 while the declaration of protectorate status over Malaya ( Johore ) in 1873 led to the first conflict with an european nation : The indonesian war of 1873/74 !!
Here is a map of Japan's colonial expansion in 1875, just after the war with the dutch empire :

- Colonial 1875.png (224.19 KiB) Viewed 10741 times
After 1874 though, as Japan was facing an economical crisis due to coal shortages and was later drawn into another major war, interest in the colonies dwindled and no major endeavour in this area was undertaken until early 1880 when it bacame paramount to gain access to some harbour in the southern indian ocean and along the south western coast of Africa.
Military : Japan at war !After the initial buildup and modernization of the Japanese armed forces not much had changed during the early years appart from the creation of a marine corp of 4 divisions and a few mountain specialists. In 1872 with the advent of the breech loaded rifles and some other technologies from the West the land force were once again trained in the use of their new equipment while new and better heavy artillery battalions were progressively introduced. The navy received its first screw driven frigates as well as new steam powered transport squadrons.
While the army and navy had been maintained up to date and trained following the counsels of the best French and German advisors it had never yet seen any real action, appart from a few petty colonial engagement in the Jungle of Borneo and later in Malaya, and the imperial general command was itching for some major conflict that would put its new toy to the test !!
Occasion arrose by the end of 1873 when a dispute with the Dutch over the ownership of Penang ( Part of the Malayan Peninsula ), which the Japanese intended to include in their protectorate over Johore kingdom, degenerated into a major crisis between the two countries : Japan remained inflexible, ultimatum were sent and by september 1873 war was unavoidable !
It was a pretty one sided affair as the dutch were fighting much farther from their home base than the Japanese imperial forces. Still, most of Europe had their eyes fixed on the conflict as interested observer : for the first time in the modern history an Asian nation was waging a war against a western power !!
As soon as october marines divisions landed in the Sulawesi archipelago while Japanese expeditionnary forces crossed the border from Sarawak and Kuching into southern Borneo.
Main japanese armies were to land in Sumatra, Java and the Celebes under cover of the 1st and 2nd imperial warfleet.
The first engagement of the war took place on the 11th of september 1873 when the 2nd fleet under command of Kaigun Kamawura Sumiyoshi intercepted an ennemy fleet of two frigates squadron in the strait of Sunda : The engagement was short and brutal and, after losing one of their frigates to the deadly fire of the Japanese warships, the dutch took refuge back inside Batavia harbour and were unable to interfere with the Japanese landing of the 4th army in Bandung !
Progress were exceedingly fast, despite the harsh conditions, as the Dutch had very little to oppose to the massive Japanese invasion force. With one notable exception though as the 4th army met stiff resistance around Batavia were the dutch had a strong and elusive army of mixed regulars and natives under leadership of a very able general ! However, after a few months and the dispatch of some reinforcements the dutch were finally cornered and crushed in a serie of battles near Malang and Bali.
By june of the next year, as the monsoon season was about to start again, most of the dutch east indies had fallen to the Japanese imperial forces just as the news of a war between Prussia and the Netherlands broke out !
The dutch had no other options than to sit at a table and start negociating for a peace deal out of the war : Japan had prevailed !!
In PON, the AI can sometimes be very stubborn and the warscore you need to get a colonial area is mostly dependent on the number of provinces rather than their real economic or strategic value? That's why the dutch kept on offering both Curaçao and Paramaribo, two very nice and rich colonies with a total of 7 sugar plantations, 4 exotic fruits and 3 tobacco (though quite far from Japan), but would not accept to let go of a barely inhabited large piece of jungle like Borneo where the only useful ressource at that time was a single coffee farm ( petroleum is useless in 1874 ). So I accepted their rather stupid offer and then scripted an exchange of provinces.
So, in july 1874 japan became the official owner of the totality of Borneo Island to the great joy of the Japanese high command who now had enough acres of prime untamed jungle to train the whole Japanese army in tropical warfare !!
In Japan, the population received the news of the swift victory with both pride and much satisfaction. Many were now urging the government for a new campaign and there were talk about an invasion of korea !
However, the Tairo was still hesitating to engage so soon in another major conflict : the economy was in difficulty due to lack of coal and it had became the top priority. But most of all, China was much stronger than the Netherlands and, in case of a Japanese invasion, the chinese would be fighting to defend their homeland !!
China at the time was, at least on paper, the 7th world military power just ahead of Japan. Their land army was estimated to be slightly larger than the Japanese one. Of course, the imperial army, trained and equiped in the western fashion would certainly have some qualitative and technological edge but some advisors pointed out, not without reason, that after fighting for so many years a bloody civil war most of the Chinese banners would certainly be formed of a large number of battle hardened veterans !! Besides, The chinese had just a few years ago repelled a Russian invasion in Manchuria wich astonished the world at large !
In February 1877 though, the aftermath of the Satsuma Rebellion, led by dispirited former Samouraïs and some hardliners disappointed by the imperial policy, compelled the imperial court to radically change its view about the Chinese question : While the rebels were easily crushed, the imperial advisors aknowledged at last the great discontent among the military and many feared that such events could repeat themeselves in the future. At the same time the economic situation was much better and the coal shortages were nearly under control.
So, from March 1877 to early January 1878, secrets plans were made for a surprise invasion of Korea and China : Fleets were refitted in the main naval bases ( With the addition of a new class of Ironclad frigates and some modern light cruisers), troops were drilled and trained on a regular basis, Merchant capacity in Northen Asia maritime trade area was more than doubled in prevision of the need to supply future operations.
On March 23, 1878, under cover of the night, the 1st and 2nd Marine divisions were landed a few kilometers outside Seoul with the mission to secure Gyongbokgung Palace and "liberate" the Joseon royal family before morning.
The following day with the opening salvoes of the Fuji and the Yamato the first part of operation "Wakisashi" started officially : the 2nd Army group (over 400 000 men ) landed in Pyongyang, Kimchaek, Wonsan and Pusan with order to occupy Korea within a month and then set up a defensive line behind the Yalu river to await the chinese counterattack.
By the end of May, the first Chinese units were spotted on the other side of the Yalu river and a few cavalry units were even able to cross the Japanese defensive lines unimpeded (I hate inactive leaders ) to wreck havoc in the imperial supply lines obliging the 4th army to play a game of cat and mouse for over 2 months, while garrisoning the main cities, before the situation could be brought back under control.
Throughout July, after concentrating huge forces in the region of Liaoyang ( stack of about 13000 power ) the chinese launched a serie of bloody assaults against the entrenched japanese positions in Yalu : The 2nd army under command of general Arimoto and supported by elements of the 1st and 3rd armies was able to repel the chinese inflicting horrendous casualties to the assaillants but barely holding the position. Finally, in the first days of August the outnumbered remnants of Arimoto's troops were decimated by the chinese cavalry after breaking under a third and furious chinese all out attack : The Japanese defensive line had been overwhelmed !!
However, at this very moment, part two of operation "Wakisashi" was under way with the deployment of the 350 000 men of the first army group in the regions of Tianjin, Jinan and Liaoxi under command of general Saigo Takamori : The attack on Korea had been a large diversion to draw the main Chinese force away from Beijing !!
The 7th army, after taking Jinan and pushing back a second smaller chinese force was able to move quickly north to besiege Beijing while the 5th army in Liaoxi would provide support and try to hold and delay the main chinese army now retreating from Korea. Tianjin with its harbour and fortress was key to the supply of the whole Japanese army in the area and the siege was under direct supervision of Takamori himself while the 6th army was still able to support the troops besiegeing Beijing ?
The armies in Korea, now free to go back on the offensive poured on the chinese side of the Yalu river quickly taking Mukden and Harbin ( chinese strategic cities ) and moving west toward Beijing themselves.
The fortress in Tianjin surrendered to Takamori in early september allowing japanese supply vessels to use the harbour thus greatly increasing the situation of the imperial expeditionnary force. At the same time the chinese were repelled, with heavy losses on both sides, during the first battle of Liaoxi just as a second chinese army ( 8000 power ) appeared north of Beijing.
Further south, imperial marines after securing Tabei and Tainan were now occupying Canton. Chinese national morale was at its lowest since the beginning of the campaign especially after losing both Tianjin and Mukden and most battles were now turning to the advantage of the Japanese imperial army ( especially since I tried to stay entrenched and on the defensive to compensate for being badly outnumbered ).
Throughout the month of october the Chinese attacked both Beijing and Liaoxi in an attempt to relieve their besieged capital but were decimated and repelled by the concentrated fire of the Japanese heavy artillery.
Finally, after a lull in the chinese offensive, the 7th army lauched a decisive assault against Beijing taking the city on the last days of November. Chinese morale plummeted and the japanese armed forces launched a serie of deadly attacks despite the terrible weather conditions . The last battle of the war took place near Jirim, Manchouria, in early January, where the remnants of the chinese army had been surrounded !!
By the end of the war the chinese army had been completely anihilated : according to the F10 screen they had only 12% of our land force left when they had started with 110% of Japan's strength.
After such a complete victory, I felt I could script my own version of the
treaty of shimonoseki especicially since Japan's international standing in game was much better than in the real world in 1895 ! The chinese were proposing to lease us Lushun ( Port Arthur ) and to abandon any claim on Korea which would become a Japanese protectorate.
Of course the Russian tried to interfere but being quite isolated on te diplomatic scene and in the middle of another endless war with the Austrian empire it just amounted to a lot of empty threats ! Anyway, since the japanese occupation of the Kuriles Islands, Russo Japanese relations had never been good to say the least !!
Japan was now at peace, or so thought the Imperial court as in April of 1879 the emperor received a peace offer from
Prussia ! 
. Nobody in the empire could even tell why and how we were now at war with the german but it was a fact ! (I sometimes don't read completely the turn log and we had been at war with Prussia for several turns without me noticing !).
We were losing the war because the Prussian who also had passage rights in France had been capturing our assets there ( coal mines, wine farms etc...). Not sure this is really WAD but it felt pretty unrealistic for the french to allow the Prussian to roam their territory at will capturing Japanese investments.
It didn't take long for the Japanese to retaliate by capturing the whole Prussian oversea empire which only amounted to a few provinces gained over the French but it was far from sufficient to get any positive warscore.
Only solution would be to send an expeditionary force to Europe and recapture our french investments : this proved the difficulty to transport large force to the European theatre without harbours in which to recoal the fleets along the way. This was the main reason why colonial and diplomatic focus changed around this time period.
After a few skirmishes with the Prussian, Japan was finally able to recapture its french industries and quickly signed a peace deal before the german could overwhelm the japanese expeditionnary forces in France. We accepted to pay them reparations for a few years despite being ourselves the actual winner of the war and they agreed on the second attempt !!
As a bonus though we were able to build 3 new coal mines while the Prussian were occupying our french ones and , since we were able to get back all our french investments at the end of the war, we had just increased our coal mines total to 39 ( 3 over the forcepool limit for Japan at the time ).
The rest of the world :GB was still number one but not for long as Japan and the US were catching fast. After coexisting with the confederates states for a few years, the USA had finally reunited. Austria and Germany were the dominant states in Europe. France and Italy were only secondary powers after being humiliated several times by Austria and Germany. The Russians were mainly concentrating their efforts in Siberia and Central Asia but had regular fits with the Austrian and the Ottoman Empire which had been pretty much locked in perpetual war either with the Russian or the Austrian.
Summary : By the end of the period, Japan, at last, had succeeded at becoming one of the greatest power in the world, second in industrial capacity and overtaking France in military might ! Many of the western countries had accepted to renegociate the unequal treaties and accepted the empire as an equal !