merchant ships arrived in China, then under the Qing Dynasty, as part of the Royal Prussian Asian Trading Company of Emden, in the 1750s. Early diplomatic relations In 1859, following China's defeat in the Second Opium War, Prussia sent the Eulenburg Expedition to negotiate commercial treaties with China, Japan and Siam. On 2 September 1861, Friedrich Albrecht zu Eulenburg and a representative from the Zongli Yamen signed the Treaty of Tianjin, which opened formal commercial relations between China and Prussia, which represented the German Customs Union. Prussia would later on become the dominant and leading part of the newly founded German Empire. The treaty would govern Sino-German relations until World War I, when the Republic of China repudiated the treaty unilaterally. During the late 19th century, Sino-foreign trade was dominated by the British Empire, and Otto von Bismarck was eager to establish German footholds in China to balance the British dominance. In 1885, Bismarck had the Reichstag pass a steamship subsidy bill which offered direct service to China. In the same year, he sent the first German banking and industrial survey group to evaluate investment possibilities, which led to the establishment of the Deutsch-Asiatische Bank in 1890. Through these efforts, Germany was second to Britain in trading and shipping in China by 1896. In 1897, the German empire took advantage of the murder of two German missionaries to invade Qingdao and founded the Jiaozhou Bay colony. Germany took control of key points in the Shandong Peninsula. In 1898, It leased for 99 years Jiaozhou Bay and its port of Qingdao under threat of force. Development was a high priority for Berlin. Over 200 million marks were invested in world-class harbor facilities such as berths, heavy machinery, rail yards, and a floating dry dock. Private enterprise worked across the Shandong Province, opening mines, banks, breweries, factories, shops and rail lines. In 1900, Germany took part in the Eight-Nation Alliance that was sent to relieve the Siege of the International Legations in Beijing during the Boxer Uprising. China paid a large annual indemnity. During the Xinhai revolution, revolutionaries killed a German arms dealer in Hankou as he was delivering arms to the Qing. Revolutionaries killed 2 Germans and wounded 2 other Germans at the battle of Hanyang, including a former colonel. Sino-German cooperation (1912-1941) The German military had a major role in Republican China. The German Navy's East Asia Squadron was in