Photographs depicting members of the Ross and Dierdorff families, including images of the Reverend William H. Dierdorff, his wife, Emma Ross Dierdorff, and his brother, Ainsworth W. Dierdorff, as well as the Tualatin Plains Presbyterian church. William H. Dierdorff (1849-1903) emigrated to Oregon with his family in 1856. He became pastor of the Presbyterian church in Tualatin Plains after the death of the Reverend George Ross in 1894, and married Ross's daughter, Emma Ross (1870-1960).

Diaries, notebook, address book, and cashbook of William H. Dierdorff (1849-1903), and photographs and postcards relating to the family of his son William H. Dierdorff (1898-1975). Dierdorff emigrated to Oregon in 1856, and after working as a civil engineer and draftsman, became a Presbyterian minister.