Highest Welsh population share, US counties · 2010
US counties ranked by the share of all residents who are Welsh ancestry (2023 American Community Survey). A concentration measure: Welsh residents as a percentage of total population. Oneida County, Idaho leads at 15.1%. 2,972 counties qualify in total. Pennsylvania carries 6 of the top 25 entries.
UPDATED 2026-06-06 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES
Frequently asked
Which county has the highest welsh share?
Oneida County, Idaho ranks #1 with 15.1% (2010 American Community Survey).
What are the top 5 counties by welsh share?
Oneida County, Idaho, Lackawanna County, Pennsylvania, Wyoming County, Pennsylvania, Mineral County, Colorado, Susquehanna County, Pennsylvania.
How many counties are in this ranking?
2,972 counties qualify after filtering for population minimums and data availability. The ranking covers 2010 ACS 5-year data.
How is welsh share measured?
Share of all residents who are Welsh ancestry (Ancestry, ACS detailed tables). Source: US Census Bureau, American Community Survey 5-year estimates (2010).