Curzon Line was the eastern boundary of Poland proposed in 1919, after World War I, by Lord George Curzon, a British diplomat. In the late 1700’s, Poland had been divided among Austria, Prussia, and Russia. The Curzon Line was to be the frontier between Russia and a new Poland. The two countries had already been at war over their borderlands in 1919, and both rejected the plan. The Treaty of Riga in 1921 ended the Russo-Polish War and moved the border east of the Curzon Line. Poland’s eastern boundary was set roughly at the Curzon Line in 1945, after World War II.
See also Curzon, Lord.