The legacy of Marcus and Narcissa Whitman is still hotly debated.
The Whitmans were regarded as an inspiration by many Christian groups in the 19th century. The Whitman Seminary was established by admirers on the site of the mission as a testament to their ministry. That institution was later moved to Walla Walla and became Whitman College.
Some historians and admirers have regarded Marcus Whitman as the savior of Oregon, arguing that his round-trip journey in 1842-43 was intended to alert U.S. governmental authorities to the threat being posed by the British in the area. This was a time during which Texas dominated much of the political discourse; Whitman helped to bring Oregon necessary attention.
The Whitman supporters find it hard to understand how anyone could be critical of selfless missionaries who gave their lives to improve the existence of others. Without the Whitmans’ efforts, the Cayuse would not have profited from modern medicine and education. Even if native life were disrupted, that was a small price to pay for the opportunity of salvation through Christianity. The fact that the religious overtures were largely ignored was not the Whitmans' fault.
Critics, however, argue that good intentions are not enough. The Whitmans’ impact on Cayuse society was not just negative, but ultimately fatal.
The Cayuse had for generations followed the seasonal offerings of nature in hunting, fishing and gathering. The Whitmans ended this traditional lifestyle and insisted upon an agricultural existence. Their purpose was to assure that the natives remain in proximity to the mission where religious instruction could be pursued; it would have been difficult to influence the lives of wandering people.
Most accounts seem to indicate that the Whitmans, particularly Narcissa, really did not respect the Cayuse. No effort was made to accommodate traditional ways or appreciate cultural differences.