The Yangtze Patrol, from 1854 to 1941, was a prolonged naval operation to protect American interests in the Yangtze River's treaty ports. Initially the patrol was carried out by ships of the United States Navy's East India and Asiatic Squadrons. In 1922, the "YangPat" was established as a formal component and assigned to the Asiatic Fleet. Under the "unequal treaties", the United States, Japan, and various European powers were allowed to cruise China's rivers. They also patrolled coastal waters, protecting their citizens, their property, and their religious missions. The Yangtze is China's longest river, and very important to commerce. Ocean-going vessels were able to proceed as far upstream as the cities of Wuhan. This squadron-sized unit cruised the waters of the Yangtze as far inland as