Spain briefly became the First Spanish Republic in 1873–74, but the monarchy was soon restored. By the start of the 20th century France, Switzerland and San Marino remained the only republics in Europe. This changed when, after the 1908 Lisbon Regicide, the 5 October 1910 revolution established the Portuguese Republic. In East Asia, China had seen considerable anti-Qing sentiment during the 19th century, and a number of protest movements developed calling for constitutional monarchy. The most important leader of these efforts was Sun Yat-sen, whose Three Principles of the People combined American, European, and Chinese ideas. Under his leadership the Republic of China was proclaimed on January 1, 1912. Republicanism expanded significantly in the aftermath of World War I, when several of the largest European empires collapsed: the Russian Empire (1917), German Empire (1918), Austro-Hungarian Empire (1918), and Ottoman Empire (1922) were all replaced by republics. New states gained independence during this turmoil, and many of these, such as Ireland, Poland, Finland and Czechoslovakia, chose republican forms of government. Following Greece's defeat in the Greco-Turkish War (1919–22), the monarchy was briefly replaced by the Second Hellenic Republic (1924–35). In 1931, the proclamation of the Second Spanish Republic (1931–39) resulted in the Spanish Civil War that would be the prelude of World War II. Republican ideas were spreading, especially in Asia. The United States began to have considerable influence in East Asia in the later part of the 19th century, with Protestant missionaries playing a central role. The liberal and republican writers of the west also exerted influence. These combined with native Confucian inspired political philosophy that had long argued that the populace had the right to reject unjust governments that had lost the Mandate of Heaven. Two short-lived republics were proclaimed in East Asia, the Republic of Formosa and the First Philippine Republic. Decolonization In the years following World War II, most of the remaining European colonies gained their independence, and most became republics. The two largest colonial powers were France and the United Kingdom. Republican France encouraged the establishment of republics in its former colonies. The United Kingdom attempted to follow the model it had for its earlier settler colonies of creating independent Commonwealth realms still linked under the same monarch. While most of the settler colonies and the smaller states of the Caribbean retained this system, it was rejected by the newly independent countries in Africa and Asia,