Oh boy, I was reading the recent book out on John Bingham and the 14th Amendment and it had a long section on opposition to the Oregon Constitution by Republicans in Congress and somehow I transposed that opposition to 1865. The mind works in strange ways, at least mine does.Actually Oregon became a state in 1859. And yes, it not only had a constitution that banned slavery, but a constitution that virtually prohibited free blacks from entering. But here's the interesting thing. Even though Oregon was coming into the Union as a free state, its admittance was opposed by Republicans. And they opposed it largely because of its horribly racist constitution:
'When the Oregon issue reached the House, however, Republican opposition to admission had mounted, and only fifteen Republicans voted in favor, while seventy-three opposed, and some of the fifteen said they regretted the Negro clauses. The motives of those who opposed admission are hard to fix with certainty, but many, especially from the East, sincerely objected to the treatment of free Negroes. Abbott of Maine, for example, denounced the constitution in the strongest terms. "You may go back to the earliest monuments of the human race," he said, "... you may search the journals of barbarians and pirates,... and you will find nothing that is more infamous and inhuman than the negro section of the Oregon constitution."'
- Eric Foner, Free Soil, Free Labor, Free Men: The Ideology of the Republican Party Before the Civil War, p. 289