in the late 1800s, each of the great powers of europe – great britain, germany, france, and russia — was eager to increase business opportunities in china, the world's most populous nation and a potentially huge market for trade in order to avoid conflict, the european leaders agreed to carve the country into "spheres of influence”-specific geographic regions, or spheres, of china in which each nation controlled trade.
secretary of state john hay, concerned that u.s. merchants might be shut out, sent a series of "open door notes" to the european powers in 1899 and 1900, asking them to respect china's territory and independence. the leaders agreed to america's op…