Yes, I know all about him. He wasn't just an advocate, he wrote the exclusion laws.
Read his quote again. It's not romanticism, it's a tongue-in-cheek half-insult. He was saying the Portlanders of the 1840s were pretty wretched. He had a dry humor style of writing. He was also judgmental as shit - read the paragraphs that surround that quote.
Here's the post I linked, inlined, because the history is so important I want people to see it who don't want to click:
Interestingly, the guy who got that law put in place was the first governor of California. He also founded Linnton by mistake and created the awful Germantown Road. Thanks, first governor of California! http://en.wikipedia.org/wiki/Peter_Hardeman_Burnett
We also had immigrants who brought their slaves and they simply continued to be slaves even though there wasn't legal slavery here. Even when there wasn't legal slavery anywhere, in fact. This woman died a slave in 1874: http://offbeatoregon.com/o1110c-civil-war-didnt-end-slavery-for-oregon-woman-named-ame.html
We even had a woman actually sold in 1857, for $700. Her name was Mary Jane Holmes. http://www.salemhistory.net/people/african_americans.htm
There were quite likely others who simply weren't recorded by history.
On Peter Burnett. He was a Southerner and considered himself quite forward-thinking for being anti-slavery in the new Oregon territory. Perhaps that's true, given that slavery in the United States wouldn't be outlawed for another couple of decades. However, he was still sharply segregationist and believed that different peoples shouldn't mix. Ergo he supported efforts to allow only Europeans to own land while making every effort to keep Asians and Africans out of the state. Sadly he was too successful as we lost the vast majority of our early Asian and African pioneers to other places that were more hospitable to people not of European descent.
When he went to California and tried to do the same they told him to fuck right off. California is resultantly much more diverse.
He talks about it in his memoirs in a chapter where he spends the entire time attacking a historian in an effort to defend himself, if you'd like to hear it from the source. He wrote, "I therefore labored to avoid the evils of intoxication and of mixed races, one of which was disenfranchised."