The 15^th US Infantry first came to China during the Boxer Rebellion. The Regiment embarked from San Francisco 16 July 1900 and arrived off the Taku Bar on 16 Aug 1900.  Since they arrived too late to take part in the relief of Peking they were relegated to service around Tientsin.  From that location they, along with their allies, took part in daily expeditions against remaining Boxer forces still in the area.  In addition the acted as escorts aboard supply junks up the Pei Tao Ho River toward Peking.  By December of that same year, with their mission complete the Regiment left China for the Philippines.

Their next China duty occurred on 18 January 1912 when the First Battalion and the Machine Gun Platoon arrived at Chinwangtao.  At time the Chinese Revolution was in full swing and there were concerns the rail lines could be cut between the coast and the Peking.  Therefore the 15^th was given the task of garrisoning a number of rail stops and bridges between Chinwangtao and the capital.  This would remain their primary mission for the next twenty-six years.  On 20 August 1916 the 2^nd Battalion was reorganized in Tientsin from the 1^st and 3^rd battalions. They would remain in China until relieved by the Marines in March of 1938.

Soldiers from the Mounted Platoon

Prior to World War I, the Great Powers would conduct joint maneuvers outside of Tientsin annually. Here American and Japanese soldiers form a joint firing line.

Company formation

 Officers in the field

Conducting a conditioning hike, c. 1933