Up to 500,000 Union soldiers, or one fourth of the Union army, was born in Europe. These immigrants left their home countries for a multitude of reasons, mostly economic and political. In the United States, they envisioned a country of freedom that would allow them to pursue their goals of acquiring wealth and participating in politics. Soon immersed in the great debate over the expansion of slavery, many immigrants found themselves forced to take sides and eventually rallied around the Union flag. Ethnic Americans joined the northern army out of the same motivations as their native-born comrades, with one notable difference. By defending the Union, immigrant volunteers hoped to tear down nativist obstruction against their assimilation into society and prove their worth as full citizens. Declaring their unconditional loyalty, several groups entered into veritable competitions to raise separate regiments that would defend not only the Union but also ethnic and national pride.