Williamson County Genealogy Lookup
Williamson County genealogy records are kept at the county clerk office in Marion, the county seat in southern Illinois. With a population around 66,000, Williamson County is one of the larger counties in the southern part of the state and has a deep record collection. The county formed in 1839 from Franklin County. Coal mining brought waves of families into the area during the late 1800s and early 1900s, and many of those families left behind records that are still on file at the clerk office or at the IRAD depository at Southern Illinois University in Carbondale. Searching for genealogy records in Williamson County means working with both local and state resources.
Williamson County Genealogy Quick Facts
Williamson County Clerk Records
The Williamson County Clerk is at 407 N. Monroe St, Room 102, Marion, IL 62959. The phone number is (618) 998-2110. This office holds birth, death, marriage, and land records for Williamson County. Birth and death records at the county level begin in the late 1870s. Marriage records go back to the 1839 formation of the county. Land records also start from the early years.
Williamson County grew fast during the coal boom that started in the 1880s. Thousands of families moved in from other parts of Illinois and from out of state to work the mines. That population surge left a big paper trail. Marriage licenses, birth registrations, property deeds, and court records from that era are plentiful at the clerk office. If your ancestors were part of the coal mining workforce in southern Illinois, Williamson County records are a prime spot to look. The Counties Code (55 ILCS 5) gives the county clerk authority over these records.
Walk-in visits to the Marion office let you search indexes and order copies the same day. Mail requests need the full name, any dates you know, the record type, a check for the fee, and a copy of your photo ID. Make checks to the Williamson County Clerk.
| Office | Williamson County Clerk |
|---|---|
| Address | 407 N. Monroe St, Rm 102 Marion, IL 62959 |
| Phone | (618) 998-2110 |
Williamson County Records at IRAD
The IRAD depository for Williamson County is at Southern Illinois University in Carbondale. Call (618) 453-3040 to check what Williamson County records they have. IRAD preserves older government documents that counties transfer for long-term storage. Court records, probate files, naturalization papers, and other county documents from Williamson County may be in the Carbondale collection. Given the county's size and the population boom from mining, the IRAD collection for Williamson County could be substantial.
Research at IRAD is free and open to everyone. You can take photos of records at no cost. Staff accept mail and phone requests but limit them to two names per request. Use the IRAD holdings database to search what Williamson County records are stored at SIU before making the trip. The Local Records Act (50 ILCS 205) created the IRAD system and sets rules for preserving county records across Illinois.
Searching Williamson County Genealogy
Start your Williamson County genealogy search at the clerk office in Marion for local records. The clerk handles vital records and land files directly. For statewide birth and death records from 1916 onward, the Illinois Department of Public Health is the source. IDPH genealogy requests go by mail and take around 12 weeks to come back. The state fee is $10 per copy. If you need a record that falls between 1877 and 1916, the Williamson County Clerk in Marion is your best bet.
The IDPH page shown above is where state-level vital records requests begin. For Williamson County, the county clerk in Marion covers the local collection.
The Vital Records Act (410 ILCS 535) sets the time limits for genealogy access. Birth records open 75 years after the birth date. Death records open after 20 years. Marriage records after 50 years. These rules apply statewide, including Williamson County. The Freedom of Information Act (5 ILCS 140) covers general public records requests, but vital records have their own rules under the Vital Records Act.
- Williamson County Clerk: vital records, marriage files, land deeds
- IRAD at SIU: historical government records from the county
- Illinois State Archives: free online marriage and death indexes
- IDPH: statewide birth and death from 1916 by mail
Williamson County and State Archives
The Illinois State Archives in Springfield maintains free online databases that include Williamson County entries. The marriage index covers 1763 through 1900. The death index spans the early 1900s to about 1950. Both are searchable from home and cost nothing to use. These are good first steps before you pay for copies from the county clerk or IDPH.
Williamson County families who came for the coal mines often moved between southern Illinois counties as different mines opened and closed. A miner who started in Franklin County might have moved to Williamson County and then on to Saline County over a few years. If you cannot find a record in Williamson County, check the surrounding counties. The same clerk system works across all of them, and mining families were mobile. Also check Jackson County since Carbondale is right next door and some Williamson County residents had ties there as well.
Note: Williamson County's population peaked during the coal era and has declined since, but the records from that period are extensive and well preserved.
Nearby Counties
Williamson County is in southern Illinois with several neighboring counties that share similar genealogy resources. Families near the borders may have records filed in more than one county. Check these areas if your Williamson County search needs broadening.