Conversation so far:
What was Edward Canby's final assignment?
In August 1872, Edward Canby was posted to command the Pacific Northwest.
When did Edward Canby die?
Edward Canby died on April 11, 1873.
How did Edward Canby die on April 11, 1873?
Edward Canby was assassinated
Are there any other interesting aspects about the Edward Canby article?
He was the only United States general to be killed during the Indian Wars.
What else can you tell me about Edward Canby's final assignment?
General Canby had received conflicting orders from Washington as to whether to make peace or war on the Modoc.
Where did Edward Canby's final assignment take place?
Edward Canby's final assignment took place in the Pacific Northwest.

Question: When did it take place?
Self-contained rewrite: When did Edward Canby's final assignment in Northern California take place?