In 1844 , he headed west over the Oregon Trail to the unorganized Oregon Country . Gilliam was in charge of the wagon train at the beginning of the journey , though the wagon train later split into smaller groups . After the Whitman massacre in 1847 , the Provisional Government of Oregon organized a force of about 600 and made Gilliam colonel to prosecute the Cayuse . In 1848 , he led his forces east to engage the Native Americans , arriving at The Dalles in February . His forces pressed on to the Whitman Mission , arriving in March
Whitman massacre
Whitman massacre
Cornelius Gilliam