J.P - Does the obituary for James mention siblings or any other family members. I have been researching Leroy G.D. Bartlett born 1815 Frederick, VA.It is possible that he is related to the James W. Bartlett you were referring to. I found some notes left by my grandmother that indicate that Leroy had a brother named J.W. Bartlett who went to Iowa, but I thought the initial J was for John.I could be wrong because there are descendants with the name James also.There is also a Daniel Peter Bartlett born Jan 22, 1822 in VA, died: 7-27-1889, Leroy,Coffey, KS, who I believe is Leroy's brother, but I have no proof other than family notes. Daniel spent some time in Indiana, marriedthen ended up in Leroy,Coffey, KS. James's birth year would fit right in with Leroy and Daniel.
I have more information on the family in Oklahoma if you are interested.