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Illinois County
Warren County, Illinois
Wyatt Earp's Monmouth birthplace and Illinois's western prairie - from Monmouth's distinction as the birthplace of Wyatt Earp (the frontier lawman, gambler, and gunfighter - most famous for the Gunfight at the O.K. Corral in Tombstone, Arizona - was born in Monmouth on March 19, 1848, and the Wyatt Earp Birthplace is preserved as a historical site) to Monmouth College's distinguished liberal arts tradition (founded 1853, Monmouth College produced the Phi Beta Kappa Society chapter that gave the national organization its distinctive handclasp greeting) and a western Illinois prairie county of corn and soybean production.
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Office: Warren County Sheriff’s Office – 121 N. A Street, Monmouth, IL 61462 | (309) 734-8506. 14 officers serving roughly 18,735 residents, with search and rescue capability. Jail capacity 22 beds.
Notes: For an active emergency, call 911. The Sheriff’s Office traces to an election held July 3, 1830, when Stephen Sumner Phelps became the county’s first sheriff.
Roads & Utilities
ROADS & TRANSPORTATION
Roads: US-34/67 serve Monmouth, “The Maple City,” the county seat, part of the Galesburg Micropolitan Statistical Area.
Notes: Warren County was organized in 1825 from Pike County, which at the time comprised all Illinois territory north and west of the Illinois River; Henderson County was later split off from Warren’s western portion in 1841. Warren County is named for Dr. Joseph Warren, killed at the Battle of Bunker Hill in 1775, believed to be the first officer to die in the Revolutionary War.
Business & Permits
BUILDING & PERMITS
Office: Warren County Courthouse – 100 West Broadway, Monmouth, IL (built 1894-1895, constructed of red Portage stone, the fourth courthouse in county history). Earlier courthouses were built in Monmouth in 1831, 1835, and 1836-1841; this flurry of construction reflected genuine county-seat competition between Monmouth and the Mississippi River port town of Oquawka, which ended once Oquawka received its own county (Henderson County) in 1841.
Notes: Monmouth is home to Monmouth College and hosts the annual Prime Beef Festival the week after Labor Day, kicked off by one of the largest parades in western Illinois.
Veterans Services
VETERANS SERVICES
Office: Warren County Veterans Assistance – confirm current contact via warrencountyil.gov.
Libraries
LIBRARIES
Warren County Public Library (Monmouth) – confirm current address/phone via the county library system.
Parks & Recreation
PARKS & RECREATION
Key Assets: Monmouth College, the Monmouth Courthouse Historic District, and local parks including Monmouth Park, Harmon Park, and Citizens Lake & Campground are the county’s premier heritage and recreational attractions.
Notes: The genuine county-seat rivalry between Monmouth and Oquawka, resolved by Henderson County’s 1841 creation, is among the standout local historical facts covered in this project.
GIS & Maps
GIS & MAPS
Appraisal/Parcel Search: Warren County Assessor’s Office – confirm current contact via warrencountyil.gov.
Animal Services
ANIMAL SERVICES
Confirm current dedicated shelter contact via warrencountyil.gov; Warren County Sheriff’s Office for animal control arrangements.
Environmental & Waste
ENVIRONMENTAL / WASTE MANAGEMENT
Office: Warren County Environmental Health – confirm current contact via warrencountyil.gov.
NOTES: Warren County is the eighty-sixth county completed in Illinois’s Round 3 v2 redo, under the A+ sourced standard established for this project. The genuine county-seat rivalry between Monmouth and Oquawka is among the standout local historical facts covered in this project. All contact information above was sourced via web search as of early August 2026 and should be reconfirmed directly with the relevant office before a visit, deadline-sensitive filing, or emergency-adjacent decision.
About Warren County
Warren County is western Illinois’s frontier lawman heritage county – birthplace of Wyatt Earp and home to a liberal arts college whose Phi Beta Kappa chapter contributed to one of American academia’s most enduring traditions.
Monmouth (the county seat, population ~9,000) is where Wyatt Earp was born on March 19, 1848. The Wyatt Earp Birthplace on Third Street is preserved as a historical site, and the annual Wyatt Earp Days festival celebrates the connection.
Monmouth College (founded 1853, enrollment ~1,000) established a Phi Beta Kappa chapter that is credited with introducing the organization’s distinctive handclasp greeting to the national organization – a small but enduring contribution to American academic tradition.
All Services
Browse every category and topic available for this county.
Warren County Assessor at 100 W. Broadway, Monmouth, IL 61462, phone 309-734-8592. IL residential assessed at 33.33% of market value. Appeal to Board of Review.
Courts & Legal
Warren County Circuit Court at 100 W. Broadway, Monmouth, IL 61462, phone 309-734-7950, handles probate.
Marriage & Vital Records
Marriage licenses, divorce records, and birth & death certificates are handled by the following office(s):
COUNTY CLERK (Records, Vital Records, Elections)
100 W. Broadway, Monmouth, IL 61462
(309) 734-8592
CIRCUIT CLERK (Court Records, Marriage Licenses)
100 W. Broadway, Monmouth, IL 61462
(309) 734-5179
ELECTIONS (County Clerk)
100 W. Broadway, Monmouth, IL 61462
(309) 734-8592
Genealogy
County-level record sources
Warren County Circuit Clerk (probate/estate case files – see Probate section above).
Monmouth College Archives – regional historical research holdings.
Local societies
No dedicated Warren County genealogical society was confirmed in available directories.
Probate & Estate
Losing someone and having to deal with courts and paperwork at the same time is hard. This section won’t make that easier, but it should tell you what to expect, what it costs, and where to go – so at least you’re not walking in blind.
Where to go
Warren County Circuit Clerk 100 West Broadway, Monmouth, IL 61462 (309) 734-5179 Warren County’s seat, Monmouth, is home to Monmouth College.
Step 1: figure out which path applies
Illinois has NOT adopted the Uniform Probate Code and is not a community property state – it follows common law property principles. Illinois probate is governed by the Probate Act of 1975 (755 ILCS 5/). Two main paths:
Small Estate Affidavit – for estates where personal property (excluding real estate) is valued at $150,000 or less (raised from $100,000 effective August 15, 2025), with no unresolved debts or claims and no real estate involved. No formal court probate is required.
Formal Probate (Independent or Supervised Administration) – required when the estate doesn’t qualify for the small estate affidavit. Most Illinois probate cases proceed under Independent Administration, letting the estate representative act without prior court approval for most routine actions.
Step 2: filing for formal probate
File the decedent’s original will (if one exists) with the Warren County Circuit Clerk, where the decedent resided at death.
Petition the court to open the estate and appoint an executor (if there’s a will) or an administrator (if intestate).
The court issues Letters of Office (Letters Testamentary or Letters of Administration) appointing the representative.
Publish notice to creditors and unknown heirs as required by Illinois law.
Under Independent Administration, the representative marshals assets, pays valid debts and taxes, and distributes the remaining estate without needing court approval for each step.
File a final accounting or closing documents to formally close the estate.
What it costs
Illinois imposes its own state estate tax on estates valued above $4 million, with rates up to 16%. There is no Illinois inheritance tax.
Filing fees vary by county – confirm current amounts with the Warren County Circuit Clerk.
Most uncontested probate proceedings in Illinois can be completed within about a year.
Probate filings, estate administration, and guardianship matters are handled by the following office(s):
Public Safety & Arrests
Arrest records, inmate search, and law enforcement services are handled by the following office(s):
SHERIFF
100 W. Broadway, Monmouth, IL 61462
(309) 734-3695
Elections & Voting
Voter registration, polling locations, and elections information are handled by the following office(s):
COUNTY CLERK (Records, Vital Records, Elections)
100 W. Broadway, Monmouth, IL 61462
(309) 734-8592
ELECTIONS (County Clerk)
100 W. Broadway, Monmouth, IL 61462
(309) 734-8592
Health & Human Services
Offices & Contacts
Health services, social services, and assistance programs are handled by the following office(s):
Warren County Health Dept
(309) 734-5163
IL DCFS — Galesburg
(309) 344-2941
IL Medicaid
(800) 843-6154
OSF Holy Family Medical Center (Monmouth)
osfsaintanthony.org/monmouth
Public Health Information
PUBLIC HEALTH
Office: Warren County Health Department – confirm current contact via warrencountyil.gov.
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Last verified June 2026
County Facts
County Seat: Monmouth
Population: 17,000
Area: 541 sq mi
Established: 1825
Tier: 3
Public Records
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