Listed below are counties with the oldest average founding year (2025-26).
The county with oldest average private school founding year is Osage County, MO with 1,874.
The county with youngest average private school founding year is Walton County, FL with 2,012.
Founding Date Range: 1944
1989
Avg. Founding Date: 1969
Average Private School Founding Year By County
County
Average Year Founded
Schools with Oldest Year Founded
Rank: #11.
1874
Rank: #22.
1881
Rank: #33.
1883
Rank: #44.
1890
Rank: #55.
1891
Rank: #66.
1892
Rank: #77.
1900
Rank: #88.
1901
Rank: #9-109-10.
1905
Rank: #9-109-10.
1905
Rank: #1111.
1907
Rank: #12-1312-13.
1908
Rank: #12-1312-13.
1908
Rank: #1414.
1913
Rank: #1515.
1914
Rank: #16-1716-17.
1916
Rank: #16-1716-17.
1916
Rank: #1818.
1917
Rank: #19-2019-20.
1918
Frequently Asked Questions
What counties have the private schools with the oldest founding year?
The counties with the oldest founding year are Osage, MO (1874 average founding year), Platte, NE (1881 average founding year) and McKinley, NM (1883 average founding year).
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