Jefferson County Historical First Ancestry Data
ACS 2010-2014 data
475,496 (87.06%) out of the total population of 546,162 reported first ancestry.
| Jefferson County | % of the Total Population | Colorado | U.S. | |
| Arab | 2,014 | 0.37%, see rank | 0.39% | 0.56% |
| Czech | 5,030 | 0.92%, see rank | 0.70% | 0.47% |
| Danish | 5,439 | 1.00%, see rank | 0.82% | 0.42% |
| Dutch | 10,444 | 1.91%, see rank | 1.81% | 1.40% |
| English | 68,111 | 12.47%, see rank | 10.49% | 8.02% |
| French | 21,704 | 3.97%, see rank | 3.48% | 3.34% |
| German | 134,052 | 24.54%, see rank | 20.88% | 15.03% |
| Greek | 2,091 | 0.38%, see rank | 0.38% | 0.41% |
| Hungarian | 2,478 | 0.45%, see rank | 0.39% | 0.46% |
| Irish | 76,385 | 13.99%, see rank | 12.04% | 10.80% |
| Italian | 36,674 | 6.71%, see rank | 5.10% | 5.52% |
| Norwegian | 14,125 | 2.59%, see rank | 2.18% | 1.42% |
| Polish | 17,022 | 3.12%, see rank | 2.51% | 3.01% |
| Portuguese | 858 | 0.16%, see rank | 0.21% | 0.44% |
| Russian | 6,757 | 1.24%, see rank | 1.09% | 0.92% |
| Scotch-Irish | 8,288 | 1.52%, see rank | 1.27% | 0.99% |
| Scottish | 15,353 | 2.81%, see rank | 2.56% | 1.72% |
| Subsaharan African | 1,524 | 0.28%, see rank | 0.73% | 0.95% |
| Swedish | 16,539 | 3.03%, see rank | 2.43% | 1.27% |
| Swiss | 2,677 | 0.49%, see rank | 0.46% | 0.30% |
| Ukrainian | 1,920 | 0.35%, see rank | 0.25% | 0.31% |
| American | 26,308 | 4.82%, see rank | 5.18% | 7.12% |
| Welsh | 5,225 | 0.96%, see rank | 0.92% | 0.57% |
ACS 2008-2012 data
481,297 (89.78%) out of the total population of 536,095 reported first ancestry.
| Jefferson County | % of the Total Population | Colorado | U.S. | |
| Arab | 1,712 | 0.32%, see rank | 0.36% | 0.53% |
| Czech | 5,026 | 0.94%, see rank | 0.73% | 0.50% |
| Danish | 5,887 | 1.10%, see rank | 0.90% | 0.45% |
| Dutch | 10,145 | 1.89%, see rank | 1.91% | 1.51% |
| English | 69,687 | 13.00%, see rank | 11.19% | 8.53% |
| French | 23,355 | 4.36%, see rank | 3.75% | 3.54% |
| German | 139,458 | 26.01%, see rank | 22.06% | 15.79% |
| Greek | 2,193 | 0.41%, see rank | 0.40% | 0.42% |
| Hungarian | 2,432 | 0.45%, see rank | 0.42% | 0.48% |
| Irish | 80,810 | 15.07%, see rank | 12.52% | 11.36% |
| Italian | 35,994 | 6.71%, see rank | 5.22% | 5.66% |
| Norwegian | 14,180 | 2.65%, see rank | 2.26% | 1.46% |
| Polish | 16,918 | 3.16%, see rank | 2.55% | 3.13% |
| Portuguese | 886 | 0.17%, see rank | 0.20% | 0.46% |
| Russian | 6,133 | 1.14%, see rank | 1.15% | 0.97% |
| Scotch-Irish | 8,605 | 1.61%, see rank | 1.37% | 1.07% |
| Scottish | 16,857 | 3.14%, see rank | 2.69% | 1.81% |
| Subsaharan African | 1,004 | 0.19%, see rank | 0.64% | 0.93% |
| Swedish | 17,992 | 3.36%, see rank | 2.64% | 1.34% |
| Swiss | 2,956 | 0.55%, see rank | 0.48% | 0.31% |
| Ukrainian | 1,670 | 0.31%, see rank | 0.25% | 0.31% |
| American | 24,302 | 4.53%, see rank | 4.88% | 6.72% |
| Welsh | 4,887 | 0.91%, see rank | 0.93% | 0.60% |
ACS 2006-2010 data
483,779 (91.52%) out of the total population of 528,614 reported first ancestry.
| Jefferson County | % of the Total Population | Colorado | U.S. | |
| Arab | 1,755 | 0.33%, see rank | 0.33% | 0.50% |
| Czech | 4,637 | 0.88%, see rank | 0.78% | 0.53% |
| Danish | 6,267 | 1.19%, see rank | 0.95% | 0.48% |
| Dutch | 10,993 | 2.08%, see rank | 1.98% | 1.63% |
| English | 75,274 | 14.24%, see rank | 11.90% | 9.02% |
| French | 24,940 | 4.72%, see rank | 3.96% | 3.77% |
| German | 146,521 | 27.72%, see rank | 22.99% | 16.51% |
| Greek | 2,459 | 0.47%, see rank | 0.40% | 0.44% |
| Hungarian | 2,337 | 0.44%, see rank | 0.43% | 0.51% |
| Irish | 83,036 | 15.71%, see rank | 12.87% | 11.76% |
| Italian | 35,381 | 6.69%, see rank | 5.18% | 5.78% |
| Norwegian | 15,569 | 2.95%, see rank | 2.34% | 1.51% |
| Polish | 16,430 | 3.11%, see rank | 2.54% | 3.24% |
| Portuguese | 881 | 0.17%, see rank | 0.22% | 0.47% |
| Russian | 6,294 | 1.19%, see rank | 1.23% | 1.01% |
| Scotch-Irish | 13,390 | 2.53%, see rank | 2.21% | 1.72% |
| Scottish | 17,967 | 3.40%, see rank | 2.86% | 1.92% |
| Subsaharan African | 913 | 0.17%, see rank | 0.55% | 0.91% |
| Swedish | 19,008 | 3.60%, see rank | 2.81% | 1.41% |
| Swiss | 3,130 | 0.59%, see rank | 0.52% | 0.33% |
| Ukrainian | 1,690 | 0.32%, see rank | 0.27% | 0.31% |
| American | 21,134 | 4.00%, see rank | 4.46% | 6.28% |
| Welsh | 5,595 | 1.06%, see rank | 0.96% | 0.63% |
ACS 2005-2009 data
485,925 (91.85%) out of the total population of 529,025 reported first ancestry.
| Jefferson County | % of the Total Population | Colorado | U.S. | |
| Arab | 1,630 | 0.31%, see rank | 0.33% | 0.50% |
| Czech | 4,880 | 0.92%, see rank | 0.80% | 0.54% |
| Danish | 6,923 | 1.31%, see rank | 0.99% | 0.49% |
| Dutch | 11,064 | 2.09%, see rank | 2.06% | 1.68% |
| English | 78,636 | 14.86%, see rank | 12.26% | 9.29% |
| French | 25,951 | 4.91%, see rank | 4.07% | 3.90% |
| German | 147,514 | 27.88%, see rank | 23.49% | 16.89% |
| Greek | 2,399 | 0.45%, see rank | 0.42% | 0.45% |
| Hungarian | 2,484 | 0.47%, see rank | 0.45% | 0.52% |
| Irish | 82,621 | 15.62%, see rank | 13.00% | 12.01% |
| Italian | 36,356 | 6.87%, see rank | 5.20% | 5.91% |
| Norwegian | 16,056 | 3.04%, see rank | 2.40% | 1.55% |
| Polish | 15,777 | 2.98%, see rank | 2.56% | 3.32% |
| Portuguese | 1,042 | 0.20%, see rank | 0.22% | 0.48% |
| Russian | 6,099 | 1.15%, see rank | 1.28% | 1.04% |
| Scotch-Irish | 13,841 | 2.62%, see rank | 2.31% | 1.77% |
| Scottish | 18,404 | 3.48%, see rank | 2.90% | 1.97% |
| Subsaharan African | 1,205 | 0.23%, see rank | 0.55% | 0.88% |
| Swedish | 19,342 | 3.66%, see rank | 2.84% | 1.45% |
| Swiss | 3,014 | 0.57%, see rank | 0.50% | 0.34% |
| Ukrainian | 1,871 | 0.35%, see rank | 0.27% | 0.32% |
| American | 21,754 | 4.11%, see rank | 4.64% | 6.43% |
| Welsh | 5,572 | 1.05%, see rank | 0.99% | 0.65% |
US Census 2000 data
445,331 (84.49%) out of the total population of 527,056 reported first ancestry.
| Jefferson County | % of the Total Population | Colorado | U.S. | |
| Arab | 1,087 | 0.21%, see rank | 0.24% | 0.36% |
| Czech | 2,449 | 0.46%, see rank | 0.37% | 0.27% |
| Danish | 3,860 | 0.73%, see rank | 0.61% | 0.30% |
| Dutch | 6,408 | 1.22%, see rank | 1.12% | 0.91% |
| English | 49,453 | 9.38%, see rank | 7.68% | 5.91% |
| French | 13,581 | 2.58%, see rank | 2.24% | 2.39% |
| German | 98,982 | 18.78%, see rank | 15.70% | 10.81% |
| Greek | 1,719 | 0.33%, see rank | 0.28% | 0.34% |
| Hungarian | 1,911 | 0.36%, see rank | 0.27% | 0.32% |
| Irish | 47,796 | 9.07%, see rank | 7.36% | 6.85% |
| Italian | 27,442 | 5.21%, see rank | 3.69% | 4.59% |
| Norwegian | 12,004 | 2.28%, see rank | 1.83% | 1.15% |
| Polish | 10,243 | 1.94%, see rank | 1.56% | 2.24% |
| Portuguese | 518 | 0.10%, see rank | 0.11% | 0.33% |
| Russian | 3,530 | 0.67%, see rank | 0.69% | 0.68% |
| Scotch-Irish | 9,327 | 1.77%, see rank | 1.52% | 1.17% |
| Scottish | 10,171 | 1.93%, see rank | 1.70% | 1.12% |
| Subsaharan African | 654 | 0.12%, see rank | 0.38% | 0.61% |
| Swedish | 12,475 | 2.37%, see rank | 1.72% | 0.87% |
| Swiss | 1,674 | 0.32%, see rank | 0.28% | 0.19% |
| Ukrainian | 1,222 | 0.23%, see rank | 0.19% | 0.24% |
| American | 25,823 | 4.90%, see rank | 5.15% | 7.33% |
| Welsh | 3,095 | 0.59%, see rank | 0.49% | 0.31% |
* ACS stands for U.S. Census American Community Survey. According to the U.S. Census, if the date is a range, you can interpret the data as an average of the period of time.