Hispanics in the American Civil War fought on both the Union and Confederate sides of the conflict. Not all the Hispanics who fought in the American Civil War were "Hispanic-Americans", in other words citizens of the United States. Many of them were Spanish subjects or nationals from countries in the Caribbean, Central and South America. Some were born in a US Territory and therefore did not have the right to US Citizenship. It is estimated that approximately 3,500 Hispanics, mostly Mexican-Americans, Puerto Ricans and Cubans (Puerto Rico and Cuba were Spanish colonies) living in the United States joined the war: 2,500 for the Confederacy and 1,000 for the Union. This number increased to 10,000 by the end of the war.