RANKING · 2010 CENSUS · 500 SHOWN OF 3,130

Largest Irish population, US counties · 2010

US counties ranked by the number of residents who are Irish ancestry, from the 2010 American Community Survey detailed-origin tables. Each list covers the full eligible universe; download the complete data as CSV. Cook County, Illinois leads at 523,306. 3,130 counties qualify in total. Massachusetts carries 5 of the top 25 entries. The median across all 3,130 is 2,926.

Irish Americans: full group profile →

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SAME RANKING BYCities States Metros

RELATEDLargest American population Highest American population share Largest Arab population Highest Arab population share Largest Egyptian population Highest Egyptian population share

YEAR2010 2020 2024

RANKPLACESTATEPOPIRISH POPULATIONVS –

USUnited States11.6% of US population308,745,53835,751,133–

01Cook County, ILIL5,194,625523,306–

02Los Angeles County, CACA9,694,934424,072–

03Maricopa County, AZAZ4,689,558396,416–

04Middlesex County, MAMA1,669,979348,275–

05Suffolk County, NYNY1,546,090340,585–

06San Diego County, CACA3,282,248282,766–

07Orange County, CACA3,149,507250,388–

08Allegheny County, PAPA1,225,035248,120–

09Nassau County, NYNY1,398,939224,840–

10Harris County, TXTX5,045,026213,622–

11Norfolk County, MAMA739,749210,496–

12King County, WAWA2,344,939209,226–

13Philadelphia County, PAPA1,574,281195,849–

14Montgomery County, PAPA877,643178,537–

15Worcester County, MAMA888,502175,644–

16Clark County, NVNV2,407,226172,605–

17Essex County, MAMA826,653171,514–

18Cuyahoga County, OHOH1,232,925168,679–

19Bucks County, PAPA647,828166,515–

20Plymouth County, MAMA546,829165,580–

21Franklin County, OHOH1,361,536164,857–

22Erie County, NYNY946,741163,985–

23Riverside County, CACA2,544,916161,809–

24Delaware County, PAPA580,937159,534–

25Tarrant County, TXTX2,248,466159,388–

26Wayne County, MIMI1,769,038156,009–

27Oakland County, MIMI1,288,337155,400–

28St. Louis County, MOMO990,911153,589–

29DuPage County, ILIL934,298150,770–

30Monmouth County, NJNJ651,035146,907–

31Pinellas County, FLFL948,563141,910–

32San Bernardino County, CACA2,224,091138,700–

33Sacramento County, CACA1,618,460134,151–

34Broward County, FLFL2,013,317133,998–

35Ocean County, NJNJ673,746133,665–

36Palm Beach County, FLFL1,575,726132,733–

37Hillsborough County, FLFL1,574,115131,450–

38Hennepin County, MNMN1,284,784128,905–

39Dallas County, TXTX2,661,397128,012–

40Westchester County, NYNY1,015,743124,206–

41Will County, ILIL712,253123,997–

42Bergen County, NJNJ977,026123,693–

43Monroe County, NYNY750,506123,123–

44Fairfax County, VAVA1,167,873121,596–

45Chester County, PAPA557,116119,155–

46Hamilton County, OHOH838,418117,831–

47New York County, NYNY1,664,862117,355–

48Baltimore County, MDMD847,650116,830–

49Suffolk County, MAMA791,891115,636–

50Onondaga County, NYNY466,584107,847–

51Camden County, NJNJ535,799106,255–

52Queens County, NYNY2,358,182105,348–

53Marion County, ININ992,196105,245–

54Bristol County, MAMA593,640105,140–

55Santa Clara County, CACA1,914,391104,278–

56Jefferson County, KYKY795,222103,555–

57Pierce County, WAWA946,288102,477–

58Pima County, AZAZ1,074,685102,378–

59New Castle County, DEDE588,026102,172–

60Contra Costa County, CACA1,170,070100,252–

61Morris County, NJNJ524,251100,063–

62Macomb County, MIMI886,22199,693–

63Providence County, RIRI678,17999,460–

64Burlington County, NJNJ481,43998,694–

65Anne Arundel County, MDMD603,38098,081–

66Alameda County, CACA1,636,63096,625–

67Orange County, FLFL1,528,00295,123–

68Bexar County, TXTX2,160,08894,415–

69Hillsborough County, NHNH433,41591,187–

70Montgomery County, MDMD1,074,58290,847–

71Duval County, FLFL1,062,96390,378–

72Lake County, ILIL719,33989,892–

73Johnson County, KSKS636,90689,156–

74Middlesex County, NJNJ883,33588,529–

75Travis County, TXTX1,389,67087,783–

76Multnomah County, OROR795,39187,160–

77Snohomish County, WAWA870,65687,159–

78Wake County, NCNC1,257,23586,855–

79Milwaukee County, WIWI924,21685,701–

80Douglas County, NENE606,46085,504–

81Kings County, NYNY2,653,96384,945–

82Brevard County, FLFL663,98284,848–

83Summit County, OHOH538,37683,267–

84Jefferson County, COCO580,45183,036–

85Jackson County, MOMO732,99481,065–

86Gloucester County, NJNJ312,63880,903–

87Hampden County, MAMA464,33880,309–

88El Paso County, COCO757,04079,477–

89Rockingham County, NHNH324,07779,259–

90Lee County, FLFL875,60778,670–

91Collin County, TXTX1,297,17978,660–

92Mecklenburg County, NCNC1,233,38377,732–

93Oklahoma County, OKOK822,12577,309–

94Ventura County, CACA830,85175,690–

95Pasco County, FLFL674,51675,232–

96Orange County, NYNY417,66975,052–

97Denton County, TXTX1,069,34674,387–

98Tulsa County, OKOK698,78273,344–

99Albany County, NYNY321,22572,953–

100Kent County, MIMI675,23271,811–

101Volusia County, FLFL606,57371,655–

102Spokane County, WAWA558,34471,045–

103Dutchess County, NYNY300,70870,744–

104Dane County, WIWI590,37569,879–

105Montgomery County, OHOH539,59868,965–

106St. Charles County, MOMO426,49967,108–

107Ramsey County, MNMN541,62366,468–

108Westmoreland County, PAPA349,32466,002–

109Shelby County, TNTN910,22665,552–

110Kane County, ILIL525,75765,521–

111Sonoma County, CACA486,44464,914–

112Richmond County, NYNY501,29064,762–

113San Francisco County, CACA826,07964,487–

114Polk County, IAIA516,54664,297–

115Luzerne County, PAPA332,12663,846–

116Polk County, FLFL874,79063,723–

117Kern County, CACA927,06863,538–

118Arapahoe County, COCO673,82063,281–

119Sedgwick County, KSKS538,43362,910–

120Cobb County, GAGA793,34562,811–

121Washington County, OROR611,70862,654–

122Salt Lake County, UTUT1,220,91662,423–

123Gwinnett County, GAGA1,018,09960,642–

124San Mateo County, CACA743,56860,636–

125Cumberland County, MEME317,22259,188–

126Barnstable County, MAMA233,53958,796–

127Lucas County, OHOH423,34758,662–

128Lackawanna County, PAPA216,50258,615–

129Stark County, OHOH373,77158,384–

130Sarasota County, FLFL479,95858,309–

131Denver County, COCO740,61358,273–

132Lancaster County, PAPA563,15958,264–

133Dakota County, MNMN457,71058,134–

134Davidson County, TNTN745,90457,824–

135McHenry County, ILIL317,75157,350–

136Waukesha County, WIWI417,21056,830–

137Fulton County, GAGA1,098,79156,091–

138York County, PAPA473,19755,844–

139Lake County, ININ504,61254,906–

140Bernalillo County, NMNM667,60154,741–

141Clark County, WAWA532,11954,493–

142Washoe County, NVNV509,38654,254–

143Virginia Beach, VAVA453,73754,157–

144Seminole County, FLFL491,88453,604–

145Jefferson County, ALAL665,74253,452–

146Essex County, NJNJ896,37953,061–

147Fresno County, CACA1,035,45652,878–

148Placer County, CACA442,08152,745–

149Montgomery County, TXTX781,19452,597–

150Berks County, PAPA440,07252,307–

151Knox County, TNTN511,45352,219–

152Saratoga County, NYNY241,34352,194–

153Union County, NJNJ601,86352,101–

154Erie County, PAPA265,83250,289–

155Lorain County, OHOH323,21950,160–

156Butler County, OHOH400,12849,474–

157Atlantic County, NJNJ278,65749,188–

158Clackamas County, OROR426,28049,165–

159Harford County, MDMD266,44647,972–

160Lane County, OROR381,58447,918–

161Genesee County, MIMI401,09347,731–

162Mercer County, NJNJ399,28947,623–

163Rockland County, NYNY357,39747,471–

164Hudson County, NJNJ735,03347,046–

165Greenville County, SCSC583,12546,750–

166Passaic County, NJNJ531,62446,720–

167San Joaquin County, CACA823,81546,260–

168Oneida County, NYNY226,39245,802–

169Douglas County, COCO399,39645,609–

170Stanislaus County, CACA557,71945,309–

171Miami-Dade County, FLFL2,802,02945,237–

172Ada County, IDID546,14144,984–

173Kent County, RIRI173,49544,624–

174Manatee County, FLFL468,20044,305–

175Broome County, NYNY195,73643,809–

176Williamson County, TXTX752,82743,646–

177Larimer County, COCO377,29243,543–

178Rensselaer County, NYNY160,51043,414–

179Lake County, OHOH232,21743,284–

180Northampton County, PAPA324,41143,124–

181Somerset County, NJNJ356,48642,700–

182Lehigh County, PAPA384,38342,698–

183Marion County, FLFL442,66042,380–

184Mobile County, ALAL411,65842,278–

185St. Joseph County, ININ272,86141,235–

186Washtenaw County, MIMI370,21441,122–

187Honolulu County, HIHI988,70341,072–

188Boulder County, COCO328,56040,812–

189Sussex County, NJNJ148,06340,757–

190Adams County, COCO554,66840,661–

191Jefferson County, MOMO233,13240,477–

192Prince William County, VAVA502,96640,127–

193Allen County, ININ402,32940,071–

194Mahoning County, OHOH224,70640,063–

195Frederick County, MDMD302,88339,931–

196Madison County, ILIL263,11039,878–

197Winnebago County, ILIL283,67439,682–

198District of Columbia, DCDC693,64539,622–

199Butler County, PAPA200,16939,565–

200Collier County, FLFL417,13139,523–

201Niagara County, NYNY208,91239,511–

202Baltimore, MDMD569,99739,501–

203Washington County, PAPA210,80239,239–

204Fayette County, KYKY329,75139,145–

205Lancaster County, NENE334,04938,876–

206Santa Barbara County, CACA442,06538,755–

207Howard County, MDMD339,18338,726–

208Loudoun County, VAVA449,74938,591–

209Ulster County, NYNY183,33038,535–

210Bronx County, NYNY1,406,33238,479–

211Anoka County, MNMN381,60538,353–

212Clay County, MOMO265,03238,329–

213Greene County, MOMO309,28638,303–

214Hamilton County, ININ387,03638,147–

215York County, MEME222,43438,147–

216Linn County, IAIA232,02837,897–

217Pulaski County, ARAR404,61137,499–

218Jefferson Parish, LALA431,39837,409–

219Marin County, CACA253,69437,352–

220Hamilton County, TNTN390,83336,934–

221Lake County, FLFL456,06836,674–

222Cumberland County, PAPA277,27036,543–

223Ingham County, MIMI289,70936,494–

224Cleveland County, OKOK303,97336,261–

225Escambia County, FLFL333,83436,050–

226Anchorage, AKAK287,15535,919–

227Kitsap County, WAWA283,37435,728–

228Washington County, RIRI129,79535,335–

229Clermont County, OHOH216,97735,329–

230Guilford County, NCNC562,23435,178–

231Madison County, ALAL433,51635,003–

232Pinal County, AZAZ539,38034,953–

233Hampshire County, MAMA164,06534,854–

234Charleston County, SCSC436,20034,851–

235Washington County, MNMN286,89534,686–

236Horry County, SCSC427,55134,399–

237St. Lucie County, FLFL402,44934,368–

238Chesterfield County, VAVA397,14834,230–

239Sussex County, DEDE277,14034,097–

240Solano County, CACA455,37634,048–

241Marion County, OROR355,77734,021–

242DeKalb County, GAGA774,39433,862–

243Yavapai County, AZAZ252,55233,494–

244Cherokee County, GAGA299,27333,473–

245Kalamazoo County, MIMI263,79533,185–

246San Luis Obispo County, CACA282,36732,940–

247Beaver County, PAPA166,03232,702–

248Dauphin County, PAPA293,35132,428–

249Mohave County, AZAZ228,10232,345–

250Thurston County, WAWA304,26132,220–

251Galveston County, TXTX372,20731,981–

252Livingston County, MIMI197,31531,970–

253Carroll County, MDMD176,67731,877–

254St. Louis, MOMO278,14431,486–

255Fort Bend County, TXTX975,19131,367–

256St. Tammany Parish, LALA279,10831,345–

257Kenton County, KYKY175,77931,313–

258Medina County, OHOH185,02531,210–

259Prince George's County, MDMD970,37431,203–

260Butte County, CACA209,21131,158–

261Hernando County, FLFL221,70130,993–

262Berkshire County, MAMA128,22430,883–

263Henrico County, VAVA342,77530,724–

264Trumbull County, OHOH198,97230,396–

265Leon County, FLFL299,04830,382–

266Hunterdon County, NJNJ131,78130,209–

267Buncombe County, NCNC277,41730,205–

268Cape May County, NJNJ93,39030,162–

269Porter County, ININ176,04930,032–

270Santa Cruz County, CACA258,85229,996–

271Merrimack County, NHNH158,07829,966–

272Lexington County, SCSC317,58829,928–

273Forsyth County, NCNC401,71829,839–

274East Baton Rouge Parish, LALA456,18029,621–

275Chittenden County, VTVT169,11529,600–

276St. Clair County, ILIL250,70829,492–

277Brazoria County, TXTX419,08029,415–

278Warren County, OHOH257,18129,249–

279Spartanburg County, SCSC380,85729,088–

280Schuylkill County, PAPA145,08528,998–

281Sangamon County, ILIL194,17028,917–

282Weld County, COCO378,42628,780–

283Washington County, ARAR271,21328,727–

284Monroe County, PAPA167,17928,641–

285St. Johns County, FLFL346,32828,409–

286Jackson County, OROR221,79528,380–

287Rutherford County, TNTN386,35228,283–

288Richland County, SCSC434,95628,198–

289Cumberland County, NCNC338,47328,175–

290Alachua County, FLFL290,02827,973–

291Oswego County, NYNY118,56927,954–

292Monterey County, CACA433,72927,887–

293Onslow County, NCNC217,17527,744–

294Putnam County, NYNY99,02827,534–

295Clay County, FLFL239,59327,515–

296Shasta County, CACA181,64827,365–

297Peoria County, ILIL178,55327,364–

298Portage County, OHOH163,40427,355–

299Kanawha County, WVWV172,38127,301–

300Delaware County, OHOH242,03227,048–

301Schenectady County, NYNY162,58126,759–

302Cambria County, PAPA128,96826,736–

303Sarpy County, NENE208,30326,626–

304Arlington County, VAVA243,93126,567–

305Scott County, IAIA175,25926,518–

306El Dorado County, CACA192,32326,470–

307York County, SCSC306,88726,398–

308Penobscot County, MEME157,96726,278–

309Lubbock County, TXTX328,90626,249–

310Licking County, OHOH185,56426,219–

311Shelby County, ALAL238,55226,163–

312McLennan County, TXTX272,02025,950–

313Williamson County, TNTN272,06125,947–

314McLean County, ILIL171,41925,700–

315Blair County, PAPA119,54125,556–

316Brown County, WIWI275,80325,534–

317Ottawa County, MIMI308,45925,452–

318New Hanover County, NCNC245,95925,401–

319Smith County, TXTX252,54925,340–

320Whatcom County, WAWA236,39225,169–

321Chatham County, GAGA311,85525,051–

322Benton County, ARAR332,55424,967–

323Anderson County, SCSC219,93024,931–

324Shawnee County, KSKS178,60724,924–

325Rock County, WIWI166,47224,843–

326St. Clair County, MIMI160,48624,711–

327Jackson County, MIMI159,55224,545–

328Santa Rosa County, FLFL211,11524,283–

329Indian River County, FLFL172,79924,184–

330Kent County, DEDE194,78624,147–

331Champaign County, ILIL209,97224,099–

332Charlotte County, FLFL217,21224,096–

333Strafford County, NHNH135,04324,095–

334Fayette County, PAPA123,02123,818–

335Deschutes County, OROR213,07223,683–

336Chesapeake, VAVA255,33223,626–

337Martin County, FLFL166,27223,611–

338Utah County, UTUT759,85923,609–

339Bay County, FLFL204,47923,541–

340Tippecanoe County, ININ190,45623,518–

341Johnson County, TXTX218,04823,481–

342Fairfield County, OHOH169,75223,293–

343Monroe County, MIMI156,00423,261–

344Forsyth County, GAGA282,80523,247–

345Boone County, MOMO191,74623,228–

346Jefferson County, NYNY111,54023,186–

347Warren County, NJNJ112,95322,988–

348Citrus County, FLFL171,66622,855–

349Okaloosa County, FLFL221,81022,783–

350Johnson County, IAIA160,04422,404–

351Baldwin County, ALAL267,76122,373–

352Union County, NCNC267,67422,365–

353Harrison County, MSMS217,13622,244–

354Ontario County, NYNY113,13022,198–

355Sumner County, TNTN215,53822,070–

356Kenosha County, WIWI168,44821,584–

357LaSalle County, ILIL107,77321,580–

358Dubuque County, IAIA99,38121,538–

359Cecil County, MDMD107,13121,431–

360Boone County, KYKY145,31621,387–

361Johnson County, ININ174,26221,347–

362Hendricks County, ININ193,51021,306–

363Newport County, RIRI83,05121,260–

364Outagamie County, WIWI195,89421,244–

365Rock Island County, ILIL141,86921,002–

366Clark County, OHOH135,34020,947–

367Vanderburgh County, ININ181,99520,941–

368Benton County, WAWA221,72220,931–

369Beaufort County, SCSC204,43320,891–

370Greene County, OHOH174,32220,815–

371Kennebec County, MEME129,06720,692–

372Tulare County, CACA485,14620,686–

373St. Louis County, MNMN200,51820,661–

374Washington County, MDMD157,73120,653–

375DeSoto County, MSMS197,91820,641–

376Kootenai County, IDID191,86420,556–

377Saginaw County, MIMI187,68820,553–

378Berrien County, MIMI152,44420,430–

379Mesa County, COCO162,84520,401–

380Centre County, PAPA157,39320,295–

381Chautauqua County, NYNY124,12620,147–

382Nueces County, TXTX352,99220,098–

383Yellowstone County, MTMT172,69220,097–

384Bell County, TXTX402,24820,095–

385Elkhart County, ININ208,77420,060–

386Gaston County, NCNC246,55819,979–

387Caddo Parish, LALA224,22619,917–

388Paulding County, GAGA190,99619,871–

389Steuben County, NYNY91,85519,859–

390Mercer County, PAPA107,86019,763–

391St. Lawrence County, NYNY105,48819,743–

392Sullivan County, TNTN163,75919,673–

393Cayuga County, NYNY74,36519,589–

394Osceola County, FLFL481,71819,540–

395Columbiana County, OHOH99,37719,269–

396Minnehaha County, SDSD212,69119,249–

397Tazewell County, ILIL130,04919,248–

398Rankin County, MSMS162,18119,236–

399El Paso County, TXTX877,85819,150–

400Missoula County, MTMT123,51319,086–

401Montgomery County, TNTN249,93519,030–

402Racine County, WIWI198,91918,977–

403Davis County, UTUT381,22718,816–

404Franklin County, PAPA160,65218,736–

405Muskegon County, MIMI177,90118,681–

406Norfolk, VAVA231,01318,649–

407Durham County, NCNC347,24018,631–

408Yolo County, CACA224,41018,488–

409Hall County, GAGA226,56818,484–

410DeKalb County, ILIL101,83518,210–

411Garland County, ARAR99,69518,205–

412Morgan County, ALAL126,48318,175–

413Monroe County, ININ143,34518,106–

414Henry County, GAGA264,92218,083–

415Blount County, TNTN143,82018,006–

416Wood County, OHOH134,17617,993–

417Indiana County, PAPA82,87817,956–

418Black Hawk County, IAIA131,53217,943–

419Chemung County, NYNY80,41517,907–

420Nevada County, CACA101,91117,905–

421Douglas County, OROR111,95117,876–

422Humboldt County, CACA131,64717,875–

423St. Mary's County, MDMD116,69217,763–

424Tuscaloosa County, ALAL241,36817,718–

425Sebastian County, ARAR130,64117,691–

426Douglas County, KSKS120,92017,657–

427Jefferson County, TXTX254,32117,611–

428Winnebago County, WIWI174,21817,398–

429Yakima County, WAWA259,18517,358–

430Calcasieu Parish, LALA208,46617,242–

431Lycoming County, PAPA112,58717,178–

432LaPorte County, ININ111,29417,004–

433Iredell County, NCNC211,79816,978–

434Grayson County, TXTX153,61316,937–

435Kendall County, ILIL145,47016,924–

436Scott County, MNMN159,01716,796–

437Richland County, OHOH124,89316,794–

438Pottawattamie County, IAIA92,99616,746–

439Spotsylvania County, VAVA155,38816,738–

440Brazos County, TXTX249,08816,719–

441Androscoggin County, MEME116,48716,694–

442Orleans Parish, LALA362,15416,645–

443Delaware County, ININ113,10616,641–

444Grafton County, NHNH93,22516,489–

445Cabell County, WVWV91,18316,460–

446Berkeley County, SCSC274,66616,387–

447Lee County, ALAL189,88116,369–

448Muscogee County, GAGA202,17116,352–

449Campbell County, KYKY95,44116,347–

450Faulkner County, ARAR133,97916,313–

451Livingston Parish, LALA155,03616,261–

452Ellis County, TXTX240,86716,173–

453Cattaraugus County, NYNY75,39016,140–

454Canyon County, IDID275,12316,110–

455Clark County, ININ130,45116,094–

456Ashtabula County, OHOH96,71316,053–

457Crawford County, PAPA81,79216,052–

458Geauga County, OHOH95,67616,018–

459Cumberland County, NJNJ157,14815,984–

460Franklin County, MOMO108,09015,944–

461Cabarrus County, NCNC249,72515,944–

462Kankakee County, ILIL105,52515,942–

463Woodbury County, IAIA106,64915,917–

464Eaton County, MIMI109,58115,902–

465Pueblo County, COCO169,27715,890–

466Lawrence County, PAPA83,91115,887–

467Catawba County, NCNC170,17215,866–

468Gallatin County, MTMT128,74015,853–

469Alexandria, VAVA160,66215,846–

470Monongalia County, WVWV107,99115,826–

471Walworth County, WIWI106,12715,750–

472La Crosse County, WIWI121,33915,700–

473Cass County, MOMO115,85915,659–

474Olmsted County, MNMN166,73115,587–

475Charles County, MDMD176,59315,550–

476Calhoun County, MIMI133,40815,541–

477Jackson County, MSMS147,66615,493–

478Warren County, NYNY65,02015,493–

479Orange County, NCNC152,49815,447–

480Johnston County, NCNC256,44815,434–

481Calvert County, MDMD94,48415,431–

482Jasper County, MOMO127,42815,397–

483Parker County, TXTX184,76715,343–

484Buchanan County, MOMO83,54015,331–

485Wayne County, NYNY91,25015,277–

486Canadian County, OKOK187,18915,255–

487Lebanon County, PAPA146,38015,221–

488Washington County, WIWI139,23815,210–

489Cowlitz County, WAWA114,88515,190–

490Sullivan County, NYNY80,58615,183–

491Pickens County, SCSC139,19815,152–

492Madison County, ININ135,08815,124–

493Cullman County, ALAL94,00915,047–

494Cochise County, AZAZ126,33215,038–

495Livingston County, NYNY61,43815,027–

496Berkeley County, WVWV139,52214,922–

497Cheshire County, NHNH78,26914,818–

498Davidson County, NCNC180,18214,788–

499Tuscarawas County, OHOH92,37314,781–

500Lenawee County, MIMI97,77914,728–

SHOWING 1–500 OF 3,130

Download CSV (full list, 3,130 rows)

UPDATED 2026-09-11 · DATA: US CENSUS BUREAU DECENNIAL CENSUS

Frequently asked

Which county has the highest irish population?

Cook County, Illinois ranks #1 with 523,306 (2010 Decennial Census).

What are the top 5 counties by irish population?

Cook County, Illinois, Los Angeles County, California, Maricopa County, Arizona, Middlesex County, Massachusetts, Suffolk County, New York.

How many counties are in this ranking?

3,130 counties qualify after filtering for population minimums and data availability. The ranking covers 2010 Decennial Census data.

How is irish population measured?

Number of residents who are Irish ancestry (Ancestry, ACS detailed tables). Source: US Census Bureau, 2010 Decennial Census.