Condensed Information from Appendix 2, Table 3 (pp. 1047-1049) of the Harvard Encyclopedia of American Ethnic Groups.  Massachusetts:  Harvard University Press, 1980.
 
 

Countries	1841-1850	1851-1860	1861-1870	1871-1880	1891-1900
All Countries	1,713,251	2,598,214	2,314,824	2,812,191	3,687,564
Greece	16	31	72	210	15,979
Ireland	780,719	914,119	435,778	436,871	388,416
Italy	1,870	9,231	11,725	55,759	651,893
Netherlands	8,251	10,789	9,102	16,541	26,758
Portugal	550	1055	2,658	14,082	27,508
South America	3,579	1,224	1,397	1,128	1,075
Spain	2,209	9,298	6,697	5,266	8,731
Sweden	13,903	20,931	37,667	115,922	226,266
Turkey	59	83	131	404	30,425
U.S.S.R.	551	457	2,512	39,284	505,290
West Indies	13,528	10,660	9,046	13,957	33,066