The reduction of the Ottoman Empire in Europe is nearly completed by the two successive military conflicts known as the Balkan Wars.

In the first, the Ottomans lose almost all their European possessions, including Crete, to Bulgaria, Serbia, Greece, Montenegro, and the newly created state of Albania.

In the second, fought between Bulgaria and the remaining Balkan states (including Romania) over the division of Macedonia, the Ottomans intervene against Bulgaria and recover part of eastern Thrace, including Edirne.

The irredentism of the Megali Idea, which has remained a strong force in Greek society since independence, gains new momentum from the liberation of territory surrounding Greece and from changes in Great Power policy in the second half of the nineteenth century.

The results are conflict with the Ottoman Empire in Crete and with the Slavs in Macedonia, along with territorial gains in Thessaly and Arta.

The heightened tensions in the Balkans reach their climax in the Great War, which is sparked by the assassination of the Austrian heir-apparent by a Serb in Sarajevo, Bosnia, on June 28, 1914.

By this time, the Ottomans have lost more than four-fifths of the territory and more than two-thirds of the population of their European provinces.

The Allies begin as Britain, Belgium and France.

Turkey and Bulgaria will soon join the Central Powers, and Russia and Italy (and eventually, the US) will join the Allies.

The war will spread from Europe to Asia and Africa, making a world war of the long-anticipated Great War.

Military operations in the Great War extend from Northern Europe through Russia, the Balkans and the Middle East to Germany’s African colonies.

Germany blockades British shipping and declares unrestricted submarine warfare.

When the First World War provokes acute shortages of tungsten, molybdenum is used on a massive scale to make arms, armor plating, and other military hardware.

The war, which pits the Central Powers—mainly Germany, Austria-Hungary, and Turkey—against the Allies—mainly France, Great Britain, Russia, Italy, Japan, and, from 1917, the United States, ends with the defeat of the Central Powers, which Bulgaria had joined, and yet another reconfiguration of the Balkan polities, including the emergence of an independent Albania and the virtual creation of a Greater Serbia in the guise of the Kingdom of the Serbs, Croats and Slovenes.

Russia and Japan reach an accord over China.

During and after the First World War, the United States pursues a policy of direct intervention in Latin America, variously occupying Puerto Rico, Cuba, the Dominican Republic, Haiti, Nicaragua, Panama, and, during the Mexican Revolution, the Mexican cities of Chihuahua and Vera Cruz.

Movements in art, literature and philosophy present an aggressive, pugnacious approach to art and language.

The movement by American women to gather in ladies’ clubs leads to their finally getting the vote in the 1920s.

The actinide element group was unknown in 1871, when Dmitri Mendeleev had predicted the existence of an element between thorium and uranium.

Uranium was therefore positioned in his periodic table below tungsten, and thorium below zirconium, leaving the space below tantalum empty and, until the 1950s, periodic tables will be published with this structure.

For a long time chemists had searched for eka-tantalum as an element with similar chemical properties to tantalum, making a discovery of protactinium nearly impossible.

The element (originally called protoactinium) is first identified in 1913 by Kasimir Fajans and Oswald Helmuth Göhring during their studies of the decay chains of uranium-238 and named brevium because of the short half-life of the specific isotope studied, namely protactinium-234.

In 1917/18, two groups of scientists, Otto Hahn and Lise Meitner of Germany and Frederick Soddy and John Cranston of Great Britain, independently discover another isotope of protactinium, 231Pa, having a much longer half-life of about 32,000 years.

Hahn and Meitner choose the name proto-actinium.

(The IUPAC will name it finally protactinium in 1949 and confirm Hahn and Meitner as discoverers.

The new name means "parent of actinium" and reflects the fact that actinium is a product of radioactive decay of protactinium.)

The discovery of protactinium completes the last gap in the early versions of the periodic table, proposed by Mendeleev in 1869, and it brings to fame the involved scientists.

North Polynesia (1912–1923 CE)

Economic Consolidation and Diversification

Between 1912 and 1923, the Territory of Hawaii experienced a period of economic consolidation and diversification, driven largely by the robust growth of sugarcane and pineapple plantations. Large plantation companies, notably Dole Food Company (formerly the Hawaiian Pineapple Company), expanded aggressively, introducing innovative farming and canning techniques that bolstered productivity and profitability.

Demographic Developments and Labor Dynamics

The influx of immigrant labor continued apace, primarily from Japan, China, the Philippines, Korea, and Portugal. By this era, Japanese laborers formed the largest immigrant group, significantly shaping the islands' social fabric. Contract labor arrangements remained dominant, yet labor conditions gradually improved due to persistent worker advocacy and international scrutiny.

Rise of Labor Activism

Labor activism intensified throughout this period, marked by significant strikes, including the major sugar plantation strike on Oahu in 1920, involving Filipino and Japanese laborers. This multi-ethnic solidarity, though ultimately suppressed, indicated a growing class consciousness and laid critical groundwork for future labor rights movements in Hawaii.

Cultural Revival and Preservation Efforts

Amid rapid modernization, native Hawaiian culture underwent a revival. Efforts to document, preserve, and celebrate indigenous traditions—such as hula, traditional chants, and Hawaiian language—gained momentum, driven by influential cultural figures and organizations. This cultural renaissance fostered a stronger sense of Hawaiian identity, even as Americanization policies persisted in education and governance.

Educational Reforms and Americanization

Public education expanded notably, with increased funding and infrastructure developments, but remained focused on assimilation. English continued as the primary language of instruction, limiting the use of Hawaiian and immigrant languages. Nevertheless, education initiatives gradually broadened opportunities for local youth, shaping an increasingly literate and politically aware population.

Political Developments and Hawaiian Advocacy

Politically, the period saw intensified advocacy among native Hawaiians and disenfranchised immigrant communities. Leaders emerged from these groups, demanding improved representation, social equity, and cultural recognition within the territorial governance framework. Their efforts, though constrained by prevailing discriminatory policies, began to gain modest concessions from colonial authorities.

Public Health Initiatives

Public health remained a priority following earlier outbreaks of bubonic plague. Authorities implemented rigorous sanitation measures, vaccination campaigns, and health education programs to prevent disease recurrence. These initiatives significantly improved public health standards and infrastructure across the islands.

Expansion of Strategic Military Importance

The strategic significance of North Polynesia, particularly Pearl Harbor, continued to grow during these years. Military installations expanded dramatically, fortifications increased, and substantial investments were made in naval infrastructure. By 1923, Pearl Harbor had become a central pillar of U.S. naval strategy in the Pacific.

Infrastructure Growth and Urbanization

Honolulu's urbanization accelerated, driven by economic prosperity and population growth. The city developed modern amenities such as paved roads, electrified streetcar systems, enhanced sewage and water supply infrastructure, and improved public services, transforming it into a significant Pacific metropolis.

Conclusion of the Era

The period from 1912 to 1923 solidified North Polynesia's role as an economically vibrant, strategically significant territory deeply integrated into the United States. Amid this integration, however, emerging social tensions, cultural revival movements, labor activism, and advocacy for political rights signaled complex dynamics that would shape future developments in Hawaiian society.

Maritime East Asia (1912–1923 CE): Republics, Colonial Consolidation, and Regional Ambitions

Between 1912 and 1923 CE, Maritime East Asia—covering lower Primorsky Krai, the Korean Peninsula, the Japanese Archipelago south of northern Hokkaido, Taiwan, and southern, central, and northeastern China—is characterized by the establishment of new political systems, increased colonial consolidation, and regional ambitions intensified by the aftermath of World War I. National identities further solidify as each region navigates complex interactions of internal change and external pressures.

China: Fall of Qing, Rise of the Republic, and Warlord Era

In 1912, the Qing Dynasty collapses following the success of the Xinhai Revolution, led by revolutionary figure Sun Yat-sen. This revolution results in the establishment of the Republic of China, with Sun serving briefly as provisional president before ceding power to military leader Yuan Shikai. Yuan attempts to consolidate authority through authoritarian measures, even briefly proclaiming himself emperor, triggering widespread opposition and the fragmentation of central authority.

The ensuing power vacuum leads to the chaotic Warlord Era (1916–1928), characterized by constant military conflicts among regional warlords. Despite political turmoil, this period sees important social and cultural developments, including the influential May Fourth Movement (1919), which advocates modernization, democracy, and nationalism, significantly shaping China's intellectual and political landscape.

Korea: Japanese Colonial Consolidation and Resistance Movements

Under harsh Japanese colonial rule, Korea experiences increased efforts at cultural assimilation and economic exploitation. The Japanese administration introduces industrial and infrastructural modernization primarily benefiting Japan's imperial ambitions, while suppressing Korean identity and dissent through strict policing and cultural policies.

Resistance against Japanese rule reaches a critical juncture during the March 1st Movement (1919), a nationwide peaceful protest demanding Korean independence. This demonstration is brutally suppressed, resulting in thousands of arrests and deaths, yet it significantly strengthens Korean nationalism and leads to the establishment of the Provisional Government of the Republic of Korea in Shanghai, becoming a focal point for Korean resistance.

Japan: Postwar Expansion, Internal Reform, and Democratic Movements

Emerging from World War I as a victor aligned with the Allies, Japan expands its influence significantly, notably through gaining German territories in the Pacific and asserting greater control in China via the controversial Twenty-One Demands (1915). This imperial expansion further solidifies Japan's international status, but generates substantial resentment, especially in China.

Internally, Japan experiences a period known as the Taishō Democracy (1912–1926), marked by a relatively liberal atmosphere, increased political participation, and the rise of parliamentary governance. However, underlying tensions remain, with powerful military and conservative factions continuing to influence political decisions significantly.

Taiwan: Accelerated Development under Japanese Administration

Taiwan sees accelerated modernization and economic development under Japanese rule, particularly through infrastructure improvements and the growth of export-oriented agriculture and industry. The Japanese administration continues its assimilation policies, fostering widespread education in the Japanese language and promoting loyalty to the Japanese empire.

Resistance to Japanese authority remains limited during this period due to strict governance, but subtle forms of local identity and dissent persist, laying foundations for future nationalist movements.

Legacy of the Era: National Identities and Regional Transformations

The years 1912 to 1923 CE significantly reshape Maritime East Asia's political, social, and cultural landscapes. China transitions from imperial rule to republicanism amidst ongoing internal strife. Korea experiences deepened colonial control alongside intensified nationalist sentiment. Japan solidifies its status as a regional power with broader international ambitions, yet faces growing internal demands for democracy. Taiwan continues its transformation under Japanese colonial administration, balancing modernization with lingering local identities. Collectively, this age of turbulent change profoundly impacts regional dynamics, setting trajectories for future conflicts and transformations.

Post-Great War League of Nation mandates award to the Japanese the German-held regions of Micronesia; the Australians take over the German colonies of Papua New Guinea, Nauru and Western Samoa.

Under China's new republic, the traditional Chinese culture begins to give way to modern ideas.

Gradually this is reflected in dress.

By the 1920s, women, in particular, adopt a compromise attire.

This is the ch'i-p'ao, better known in the West by its Cantonese name, cheongsam.

In 1924, the Turkmen S.S.R.

is formed out of the Turkmen province, together with the Turkmen rayony (sectors) of the former Khorezmian Republic (Tashauz [now Dashhowuz], Takhta [now Tagta], Ilyata, Kunya-Urgench, and Porsa) and of the Bukhara Republic (Chardzhou [now Chürjew], Kerki, and part of Sherabad).

The following year, it formally becomes one of the USSR's constituent republics.

This is the first time that Turkmens experience even nominal political unity.

In August 1920, the Russian Revolution is extended to the khanate of Bukhara, and the Bukharan People's Soviet Republic is declared in October.

Early in 1921, the Soviet army captures the Tajik centers of Dushanbe and Kulob.

After the Russian Revolution of 1917, the victorious Bolsheviks reorganize Muslim Central Asia into national Soviet republics.

Muslims convoke a National Congress in Kokand and establish an autonomous government under Mustafa Chokayev, which is liquidated in February 1918 by Red Army forces sent from Tashkent.

This action provokes a prolonged resistance movement known as the Basmachi (Qorbashi) Revolt.