Gem County Museum and Historical Society, 501 East First Street, Emmett, Idaho.
Ola Ladies Club, Ola, Idaho. Sponsors of the Ola Reunion, first Sunday after Labor Day.
For cemetery records, see Ola Cemetery at Find A Grave
Idaho State University 1880 & 1900 census transcriptions 
first known as Upper Squaw Creek
The first post office in this area was "Upper Squaw Creek," established in September of 1875, by Carroll Baird. Baird homesteaded along Squaw Creek, less than half a mile west of the present-day site of Ola. 
Nellie Ireton Mills  writes that the Bairds built their cabin where the old Indian trail crosses the creek. The trail was also used by miners and others taking the short cut to, or from, Oregon and the Boise Basin. Prior to the 1875 post office, the mail was delivered by pack horse and snowshoes along the Brownlee Trail from Horseshoe Bend (Boise County) to Warren (Idaho County).
Six weeks after the post office was established, Bairds' bachelor neighbor to the north, Fred Hoffman was appointed postmaster, a postion he held until the post office closed the end of January 1877, when mail was sent to Cascade (Valley County). Mills writes that first wedding in the community was between Fred Hoffman (she calls him "Huffman") and school teacher Ella Drake on March 6, 1879.
When the post office was re-established July 1882, Baird named it Ola, "for an old Swede that happened along." 
Ola Postmaster Appointments
Post Office established July 22, 1882, by Carroll Baird; Miranda Perron, November 10,1890; Benjamin F. Shepard, February 27, 1892; George W. Smith, November 21, 1895; Benjamin Shepard, May 6, 1901; John M. Holbrook, July 18, 1903; Edward Thornton, September 28, 1906; Sherman Glenn, Oct. 25, 1908; John Babcock, Dec. 10, 1918; Palmer W. Wharton, August 10, 1917 [end of record] .