In the letter, "Cousin Ellin" is Theresa Ellen Offill, born November 25, 1845 in 
Carter County, Kentucky. Theresa married Reuben Fletcher Ross. She was the daughter of 
James Offill and Mary Louellyn Scott.

The writer of the letter, Elza Offill, was the Elza Offill who was the 
son of Allan Offill and Louise Hargett. Allan was the brother of Theresa's father, James

"Ashley", by all evidence, refers to Ashley, Illinois.

In the letter "Manda" is probably refers to Ellen's sister, Amanda H. Offill (Amanda J. Offill on the 1860 census.
Amanda was born June 8, 1852 (or 1849 per LDS). Amanda died December 2, 1926 and is buried at Maddix Cem., Carter 
County, Ky.. About 1867, Amanda married William R. James and they had 7 children. Amanda later married 
Thomas Jefferson Maddix.

In the letter, "Harve" is probably Ellen's brother John Harvey Offill, born May 17, 1835 in Lawton, KY.
He died June 16, 1911. He is recorded as being a "bachelor" and "a fox hunter".

In the letter, "James" refers to Elza's brother, James Offill, born in 1842 in Kentucky. James "went to Iowa".

There are many sources of information on the Civil War "Copperheads", as mentioned in the letter. Illinois was a stronghold of the Copperheads.
A good place to start is:

In the records of the 44th Illinois Infantry, there is a James Offill from Ashley,
Illinois. No doubt this is Elza's brother.
"My big brother Methias" was good clue to identifying the author these letters.
The roster of the 44th Illinois also lists a Sgt. Mathias W. Offill and a Pvt. Matthias Offill, one (or both) of
these references may be the "big brother Methias" mentioned in the letter. Note also that there is a listing of "Sanders Offill". 
All are listed as being from Ashley, Illinois. Strangely, Elza's "big brother" was in fact 15 years younger than Elza.

Per, Sanders A. Offill married Lourena Jane Hargett and lived in Ashley, Washington Co., Illinois. 
Aaron Sanders Offill was born in 1831 in Kentucky. He was also Elza's brother.

Per, Mathias W. Offill who was born in 1843 in Kentucky, the son of Allan Offill and
Louisa Harget. This confirms that the "Elza Offill" who wrote these letters was the son of this same Allan and 
Louisa Offill, brother to Mathias and James.

Elzaphen Offill, was born in 1828 in Kentucky, and according to, "went to California".

I'm not sure who the "Ross" is refered to in the third page of the letter. Ellen's sister, Louisa, may have married John Piatt Ross
by the time this letter was written. They were married no later than 1865. As noted earlier, Ellen eventually married Reuben Fletcher Ross.

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	Ashley Ill(?) April the 3 rd

		Dear Cousin Ellin
I received you very kind &
interesting letter yesterday dated
March the 15th  you cannot tell
how glad I was to hear that you
had got my letter for I had
began to think that you would
never get it   from the letters I
got from you & Manda & Harve
I was truly glad to know that 
you had not forgotten me & you
thought enough of me to write to
me   I have writen several letters
since I came home and have never
got any answers   only from you and
Dine I answered  Amanda letter one
week ago today  She seemed to think
that I had forgotten you all  It is
a mistake   I think of you often when
I am at work in my shop or after
my rest at night  I have thought

----------------   TRANSCRIPTION PAGE 2 ---------------

of you and wondered in my 
mind if I would ever see you
all again  I believe I will if we all
live  we are all well at this time
as far as I know   Well Cousin Ellen
I wish you had bin here last Friday 
and went with me out to mother's 
She made a dinner for James on
that day   She cooked(?) all Thursday
in and invited some of the
neighbors in  We had a nice dinner
and after the dinner was over we had
the lingest romp you ever saw   Then
at knight there was a supper
prepared in Ashley for the 44th
Ill Reg which we all went and
foretook   It was as nice a supper as
ever my eyes beheld   Next morning
on the 8 o'clock train James 
left me  I fear I shall never
see him again    He is a good 
boy   I like him though him and
I differ in politics somewhat
My big brother Methias has fell
out with me on account of my
being a Coperhead  I guess will get over it

----------------   TRANSCRIPTION PAGE 3 ---------------

Well Cousin Ellen I have told
you about all that I can think
of at present - I intend to thay(?)
by the Grace of God to met you
in heaven  The place of rest
for all that serve an love the lord
Cousin Ellen stand firm and live
up to the word of our Father who
art in heaven and you will
eventually receive a crown of life
gain admitance into that house
eternally in heaven not made
by hands   I expect to met you there
Should we never met in earth again
Cousin Ellen you may tell ?? that
I intend to write to her  I suppose because
I have not written to her she thinks
I will not write to her  I intend 
to write to everyone of the family
separately and individually so there
will be no room for gambling(?)
I have written to most of you now
and can get no nanswer only from you
Cousin Ellen ///// Tell Harve 
& Ross to write  I would like to hear from them.

----------------   TRANSCRIPTION PAGE 4 ---------------

Mother sends her love to all
give my love to all inquiring friends