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Cook County – Ancestry

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Ancestry refers to the lineage or descent of a person, family, or group, tracing back through generations to identify their origins, heritage, and familial connections. It encompasses the genetic, cultural, and historical ties that link individuals to their forebears, shaping their identity and sense of belonging. Ancestry is a multifaceted concept, intertwining biology, genealogy, history, and culture, and it plays a significant role in how people understand themselves and their place in the world.

At its core, ancestry is rooted in genetics. Each individual inherits a unique combination of DNA from their parents, who in turn inherited their DNA from their own ancestors. This genetic material carries information about physical traits, predispositions to certain health conditions, and even behavioral tendencies. Advances in genetic testing, such as DNA analysis, have made it possible for individuals to trace their biological ancestry with remarkable precision. Companies like 23andMe and AncestryDNA offer services that analyze genetic markers to provide insights into a person's ethnic composition and geographic origins, often revealing surprising connections to distant relatives or previously unknown heritage.

Beyond genetics, ancestry is deeply tied to genealogy, the study of family history and lineage. Genealogical research involves constructing family trees, documenting relationships, and uncovering historical records such as birth certificates, marriage licenses, census data, and immigration documents. This process often reveals stories of migration, resilience, and adaptation, offering a window into the lives of ancestors and the challenges they faced. For many, genealogy is a way to honor their forebears and preserve their legacy for future generations.

Cultural ancestry is another critical dimension, encompassing the traditions, languages, customs, and values passed down through generations. It connects individuals to their ethnic or national heritage, shaping their cultural identity and worldview. For example, someone with Irish ancestry might celebrate St. Patrick's Day, learn traditional Irish dance, or explore the Gaelic language, while someone with Japanese ancestry might practice tea ceremonies, study calligraphy, or observe Obon festivals. Cultural ancestry fosters a sense of continuity and belonging, linking individuals to a broader community with shared experiences and values.

Historical ancestry delves into the broader context of a family's or group's past, including significant events, social conditions, and historical movements that shaped their lives. For instance, the transatlantic slave trade, the Irish Potato Famine, or the Jewish diaspora have profoundly influenced the ancestry of millions of people, leaving lasting imprints on their descendants' identities. Understanding historical ancestry often involves grappling with complex narratives of triumph and tragedy, resilience and oppression, and the interplay of individual and collective experiences.

Ancestry also has a deeply personal and emotional dimension. For many, exploring their ancestry is a journey of self-discovery, offering insights into who they are and where they come from. It can foster a sense of pride, connection, and continuity, as well as a deeper appreciation for the struggles and achievements of those who came before. At the same time, it can raise questions about identity, belonging, and the complexities of heritage, particularly for individuals with mixed or multicultural backgrounds.

In a globalized world, ancestry serves as a bridge between the past and the present, connecting individuals to their roots while also highlighting the interconnectedness of human history. It underscores the diversity and richness of human experience, reminding us that every person's story is part of a larger tapestry woven over centuries. Whether through genetic testing, genealogical research, cultural practices, or historical exploration, ancestry offers a profound way to understand ourselves and our place in the world.

A diversification score measures the diversity of ancestries in the county. As the value appoaches 100, ancestry diversity decreases and therefore increasing the risk of a lack of cultural diversity. The ancestry diversification score for this county is:

9.36

Most common ancestry not including "Unknown" is:

Mexican

 
Ancestry Report Part I
DescriptionTotal Population American Native American Hawaiian Caribbean (Latino) Mexican Central American South American Other Hispanic African American Sub- Saharan Caribbean (Black)

Cook County5,233,70152,0475,528990168,9761,041,26956,18572,27235,530719,598233,195209,636
Illinois (in 000's)12,7843341632601,81196109661,099348291
National (in 000's)343,25113,8902,21362611,32738,8796,1814,6443,68725,8937,8527,174
DuPage County943,02214,79887122115,600111,0327,3288,9833,53429,4999,2106,327
Lake County723,13115,97692833517,213135,45310,3606,7144,70429,0369,0428,690
Will County711,57411,6217707310,406113,1923,0603,9692,85850,68220,4379,550
Kane County523,4649,58752811212,759141,5675,5884,6254,96416,9394,6913,960
Lake County504,4987,9036448715,69879,5881,8471,3542,72980,35819,27818,277
McHenry County317,0517,381313574,94738,4931,7592,0971,0473,005813560
Porter County176,1586,299230514,00514,3432174114886,077669445
Berrien County152,7105,288698901,2356,62023463045411,0985,1643,825
 
Per Cent to Total PopulationDiversity
Index
 

Cook County9.360.990.110.023.2319.901.071.380.6813.754.464.01
Illinois8.322.610.120.022.0314.170.750.850.528.602.722.28
National7.834.050.640.183.3011.331.801.351.077.542.292.09
DuPage County7.661.570.090.021.6511.770.780.950.373.130.980.67
Lake County8.922.210.130.052.3818.731.430.930.654.021.251.20
Will County8.521.630.110.011.4615.910.430.560.407.122.871.34
Kane County12.041.830.100.022.4427.041.070.880.953.240.900.76
Lake County9.341.570.130.023.1115.780.370.270.5415.933.823.62
McHenry County9.862.330.100.021.5612.140.550.660.330.950.260.18
Porter County10.403.580.130.032.278.140.120.230.283.450.380.25
Berrien County10.373.460.460.060.814.340.150.410.307.273.382.50
 
Comparisons to State Norms % to Total >= 150% % to Total < 50% 

Cook County 38.0384.7581.80158.76140.41142.98162.17131.60159.91163.77175.75
Illinois 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
National 154.75517.34789.18162.2779.93239.84158.89208.2187.7384.0891.71
DuPage County 60.0174.11101.3581.3583.09103.50111.8772.6436.3835.9029.44
Lake County 84.49102.96200.35117.05132.19190.81109.04126.1046.7045.9652.73
Will County 62.4686.8244.3771.91112.2657.2765.5177.8682.84105.5658.89
Kane County 70.0480.9392.53119.86190.86142.18103.76183.8337.6432.9433.19
Lake County 59.91102.4274.58153.01111.3348.7631.52104.86185.25140.45158.96
McHenry County 89.0379.2177.7576.7385.6873.8977.6864.0111.029.427.75
Porter County 136.75104.76125.20111.8057.4616.4127.4053.7040.1213.9611.08
Berrien County 132.43366.73254.8739.7730.5920.4148.4557.6384.52124.29109.90
 
Comparisons to National Norms % to Total >= 150% % to Total < 50% 

Cook County 24.5716.3810.3797.84175.6559.61102.0763.20182.27194.78191.64
Illinois 64.6219.3312.6761.63125.1041.6962.9448.03113.98118.94109.04
National 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
DuPage County 38.7814.3212.8450.13103.9543.1570.4134.8941.4742.6932.10
Lake County 54.6019.9025.3972.13165.3879.5668.6260.5653.2354.6657.50
Will County 40.3616.785.6244.32140.4423.8841.2337.3994.42125.5564.21
Kane County 45.2615.6411.7273.86238.7759.2865.3088.2942.9039.1836.19
Lake County 38.7119.809.4594.29139.2820.3319.8450.36211.15167.05173.33
McHenry County 57.5315.319.8547.28107.1930.8148.8930.7512.5611.218.45
Porter County 88.3620.2515.8768.9071.886.8417.2425.7945.7316.6012.09
Berrien County 85.5770.8932.3024.5138.278.5130.4927.6896.34147.83119.84
 
Ancestry Report Part II
DescriptionTotal Population Canadian British Dutch French German Italian Polish Scandi­navian Scotish/ Irish Spanish Other European

Cook County5,233,7015,42883,11116,18021,349215,670126,516198,07754,249225,3708,223198,344
Illinois (in 000's)12,78420481691061,20736442323378922459
National (in 000's)343,2511,35018,0691,8283,64224,7089,0274,6675,96920,6251,1409,563
DuPage County943,0221,80830,9516,5966,89780,33149,03548,79120,93968,8132,20755,469
Lake County723,1311,56121,9572,7235,51659,96521,49828,29917,00540,8071,34338,759
Will County711,5741,20019,3535,8244,20861,23332,09641,10911,17350,9212,28930,639
Kane County523,4641,24317,2602,4424,72550,01019,18518,13413,68329,5041,17917,507
Lake County504,49890613,7438,8532,82334,40611,41324,9445,18825,6781,60524,728
McHenry County317,05191614,0201,7482,97849,55416,58520,09411,79728,58088313,337
Porter County176,15852010,2481,8641,81021,7624,7818,8673,93216,77061811,130
Berrien County152,7105799,3912,6111,95023,3163,5254,2243,36110,1791555,882
 
Per Cent to Total PopulationDiversity
Index
 

Cook County9.360.101.590.310.414.122.423.781.044.310.163.79
Illinois8.320.163.770.540.839.442.853.311.826.170.183.59
National7.830.395.260.531.067.202.631.361.746.010.332.79
DuPage County7.660.193.280.700.738.525.205.172.227.300.235.88
Lake County8.920.223.040.380.768.292.973.912.355.640.195.36
Will County8.520.172.720.820.598.614.515.781.577.160.324.31
Kane County12.040.243.300.470.909.553.673.462.615.640.233.34
Lake County9.340.182.721.750.566.822.264.941.035.090.324.90
McHenry County9.860.294.420.550.9415.635.236.343.729.010.284.21
Porter County10.400.305.821.061.0312.352.715.032.239.520.356.32
Berrien County10.370.386.151.711.2815.272.312.772.206.670.103.85
 
Comparisons to State Norms % to Total >= 150% % to Total < 50% 

Cook County 65.6542.1757.4749.4043.6484.89114.4456.8869.7989.75105.49
Illinois 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
National 248.99139.8099.00128.4876.2392.3641.1195.4297.38189.7777.56
DuPage County 121.3687.16130.0388.5790.21182.61156.45121.85118.26133.70163.74
Lake County 136.6580.6470.0092.3787.81104.40118.33129.0491.46106.09149.20
Will County 106.7572.23152.1571.6191.12158.40174.6986.16115.98183.76119.86
Kane County 150.3187.5786.72109.31101.17128.71104.75143.4491.35128.6793.10
Lake County 113.6872.34326.2167.7672.2279.45149.5156.4382.49181.74136.44
McHenry County 182.89117.44102.49113.74165.51183.70191.64204.18146.09159.10117.10
Porter County 186.86154.50196.70124.43130.8295.31152.21122.49154.29200.41175.88
Berrien County 240.01163.32317.84154.63161.6881.0683.64120.77108.0357.98107.22
 
Comparisons to National Norms % to Total >= 150% % to Total < 50% 

Cook County 26.3730.1758.0538.4557.2591.92278.3659.6171.6747.30136.02
Illinois 40.1671.53101.0177.83131.19108.27243.24104.80102.6952.70128.94
National 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
DuPage County 48.7462.35131.3468.93118.34197.71380.55127.69121.4470.45211.12
Lake County 54.8857.6870.7171.90115.20113.04287.83135.2493.9255.91192.38
Will County 42.8751.67153.6955.74119.55171.51424.9290.30119.1096.84154.54
Kane County 60.3762.6487.6085.08132.72139.36254.80150.3393.8067.80120.04
Lake County 45.6651.75329.5152.7494.7486.02363.6659.1484.7195.77175.92
McHenry County 73.4584.00103.5388.53217.13198.90466.15213.98150.0283.84150.98
Porter County 75.05110.51198.6996.84171.62103.20370.22128.37158.44105.61226.77
Berrien County 96.39116.82321.05120.36212.1187.77203.44126.57110.9330.55138.25
 
Ancestry Report Part III
DescriptionTotal Population Chinese Filipino Japanese Korean Vietnamese South Central Asian South East Asian Other Asian Middle Eastern Other Ancestry Unknown

Cook County5,233,70184,52970,77012,49437,51315,877138,28725,52318,66748,063674,404359,831
Illinois (in 000's)12,7841371301860272914933751,5811,775
National (in 000's)343,2514,4613,0107931,5411,9135,4521,6431,2291,93147,32251,000
DuPage County943,02215,65116,9231,4134,8333,48264,5858,1004,2027,783137,69899,112
Lake County723,1319,51910,6231,5636,3971,37025,8682,5882,1023,220101,10480,893
Will County711,5745,4369,5012241,60199921,8162,0682,0283,49791,17386,568
Kane County523,4641,2316,1103141,2015118,6552,3269291,57963,11757,299
Lake County504,4981,0231,6261505318422,3575095161,67458,45354,767
McHenry County317,0517273,0311489724382,49657656087535,44250,822
Porter County176,158429473585118263425722842520,48637,398
Berrien County152,710428545903627389631318321415,87233,225
 
Per Cent to Total PopulationDiversity
Index
 

Cook County9.361.621.350.240.720.302.640.490.360.9212.896.88
Illinois8.321.071.010.140.470.212.270.390.260.5912.3713.89
National7.831.300.880.230.450.561.590.480.360.5613.7914.86
DuPage County7.661.661.790.150.510.376.850.860.450.8314.6010.51
Lake County8.921.321.470.220.880.193.580.360.290.4513.9811.19
Will County8.520.761.340.030.220.143.070.290.290.4912.8112.17
Kane County12.040.241.170.060.230.101.650.440.180.3012.0610.95
Lake County9.340.200.320.030.110.170.470.100.100.3311.5910.86
McHenry County9.860.230.960.050.310.140.790.180.180.2811.1816.03
Porter County10.400.240.270.030.030.100.360.150.130.2411.6321.23
Berrien County10.370.280.360.060.240.050.590.200.120.1410.3921.76
 
Comparisons to State Norms % to Total >= 150% % to Total < 50% 

Cook County 151.21133.28166.30152.40141.41116.15126.59136.31156.11104.2049.51
Illinois 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
National 121.6886.44160.9195.48259.7869.82124.24136.8995.61111.49107.00
DuPage County 155.39176.88104.38108.97172.12301.05222.97170.30140.30118.0875.69
Lake County 123.25144.80150.57188.0988.31157.2592.90111.0975.69113.0680.56
Will County 71.52131.6121.9347.8465.44134.7775.44108.9283.54103.6187.61
Kane County 22.02115.0541.7948.7845.5172.68115.3567.8351.2897.5178.83
Lake County 18.9931.7720.7122.3877.8020.5426.1939.0956.4093.7078.18
McHenry County 21.4794.2332.5265.1864.4034.6147.1667.5046.9190.40115.44
Porter County 22.8026.4722.946.1648.1615.8237.8749.4741.0194.04152.89
Berrien County 26.2435.1841.0650.4022.2825.7953.2145.8023.8284.05156.69
 
Comparisons to National Norms % to Total >= 150% % to Total < 50% 

Cook County 124.27154.18103.35159.6254.44166.36101.8999.58163.2793.4746.27
Illinois 82.18115.6862.15104.7438.49143.2380.4973.05104.5989.7093.46
National 100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00100.00
DuPage County 127.70204.6264.87114.1366.26431.20179.46124.41146.73105.9170.74
Lake County 101.29167.5093.57197.0034.00225.2274.7781.1679.17101.4175.29
Will County 58.78152.2413.6350.1025.19193.0360.7279.5787.3792.9481.88
Kane County 18.09133.0925.9751.0917.52104.1092.8449.5553.6387.4673.67
Lake County 15.6036.7512.8723.4429.9529.4121.0828.5658.9984.0473.06
McHenry County 17.64109.0120.2168.2724.7949.5737.9649.3149.0781.08107.89
Porter County 18.7430.6214.256.4518.5422.6630.4836.1442.8984.35142.89
Berrien County 21.5740.6925.5152.798.5836.9442.8233.4624.9175.39146.43


Sources: STI: PopStats, Circa April 2025