I too am looking for information on Jonathan A. Dann and Catherine Letteer.I believe that they were the parents of Nelson L(etteer?) Dann who was born abt 1855 and probably died bef 1910.
I have seen another source that has Jonathan married 5 times, but the dates listed by this source don't add up correctly.
I believe that I have found Jonathan in the 1880 Census in Lone Tree Township, McPherson Co., Kansas with wife Elizabeth, their children and a daughter-in-law and grandson that I think might be the wife of Nelson.
Can you tell me anything else about your Jonathan??