According to Bloomberg, 15.68 percent of Americans have German ancestry and over 60,000 of them live in Bismarck, North Dakota.
The greatest German influx occurred during the mid-19th century due to high unemployment and unrest in Europe. Many famous Americans are of German descent including the likes of David Letterman, Ben Affleck and Sandra Bullock.
11 percent of the U.S. population claim Irish descent and the highest concentration can be found in Ocean City, New Jersey. The Irish potato famine brought around 4.5 million Irish people to American shores. 22 U.S. presidents were of Irish descent and famous Irish Americans include John F. Kennedy and Neil Armstrong. Mexican ancestry follows close behind at 10.58 percent. Americans with Mexican ancestry are most concentrated in Laredo, Texas and notable people include Joan Baez, Eva Longoria and Jessica Alba.
This chart shows the highest ancestral concentration in U.S./metro areas in 2014
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