Passing along info I have found. Thomas Ross b) Chester Co.,PA,m) Margaret Van Horn McElfresh , May 8,1850,Morgan Co.,OH..........Son Joseph b) 1851,Morgan Co.They are next found in Clackamas Co.,OR...Having arrived Oct 1852.They went there to claim OR Donation Land,which was offered to "certain whites & half-breed Indians"...Dec 6,1863 he signed an Oath of Allegiance ( more about that as info comes in ) 1870 Census of Clackamas , Marquam,OR, shows Margaret with the following children :.....her daughter Catherine married Isaac Stephens 1865 in OR......... children of Thomas & Margaret: Joseph ..19 OH Mary .....15 OR John...... 13 OR William ..12 OR Lincoln.... 9 OR George.... 6 OR Clara....... 4 OR Margaret.. 2 OR Mar 8 1870 land was issued to Margaret Ross widow & hers-at-law.........Margaret married Ole Hansen1873,Clackamas Co.,OR Barb in MI

To add to what Barb has located regarding Thomas Ross of Morgan County, OH, I wanted to pass along info. from an obituary for Mary Elizabeth Ross Marquam, dau. of Thomas and Margaret Ross, who left Morgan County, OH to go to OR in 1852. She was the 4th of 11 children and was b. 17 Jan 1855 at Marquam, OR and married James E. Marquam on June 1, 1876. Mary Elizabeth died on 2 Dec 1938 in Tillamook, OR. Children surviving were: two sons, J.C. Marquam of Portland, O.A. Marquam , two daughters, Mrs. A.T. Whitten of Dufur and Mrs. Hugh Barber of Tillamook. Cheryl Arver