Lewis and Clark County
Founded: 1865
County Seat: Helena
Largest city: Helena
The county was established on June 2, 1865, as one of the nine original counties of the Territory of Montana.
It was first named Edgerton County, after the first territorial governor, Sidney Edgerton, 1864-1865, then renamed on March 1, 1868 in honor of explorers Meriwether Lewis and William Clark
As of the 2020 census, the population was 70,973
Helena, MT
Cities, Towns and Other Communities
Cities
Helena ~ East Helena
Census-Designated Places
Augusta ~ Canyon Creek ~ Craig ~ Gilman ~
Helena Valley: Northeast, Northwest, Southeast, West Central and West Side ~
Lincoln ~ Marysville ~ Milford Colony ~ Rimini ~ Unionville ~ Wolf Creek ~ York
Other Unincorporated Communities
Austin ~ Bald Butte ~ Birdseye ~ Canyon Ferry ~ Dearborn (part w/in Cascade Co.) ~
Fort Harrison Army Air Park ~ Four Range ~ Frontier Town ~ Gearing ~ La Chapelle Place ~
Nelson ~ Silver City ~ Stoner Place ~ Weed ~ Wilborn ~ Winston
Ghost Town
Marysville
Surrounding Counties
Broadwater County - southeast
Cascade County - east
Flathead County - northwest
Jefferson County - south
Meagher County - east
Powell County - west
Teton County - north
SEARCH OUR SITES
Contact Us
Submit an Obituary
with our automated form
Join our Genealogy Trails Western States Mailing List
to get email notices when our county sites are updated.
For the Western States of :
Colorado -- Idaho -- Montana -- Utah -- Wyoming
Visit our Montana State Site
Visit our National Site
Copyright © Genealogy Trails
2025
All data on this website is Copyright by Genealogy Trails with full rights reserved for original submitters.
No data is to be copied to other websites without permission
