1. In 1850, the Oregon Territory officially banned slavery, becoming the first state or territory to do so through legislation. This move was significant in advancing the abolitionist cause in the United States.

2. On November 28, 1864, a group of settlers were attacked by Native Americans in what is now known as the Battle of Adobe Walls. This conflict, which took place in present-day Texas but involved several Oregonians, was one of the last major battles between Native Americans and white settlers in North America.

3. The first documented ascent of Mount Hood, the highest peak in Oregon, was made on November 28, 1857, by a group of six men led by Henry Pittock. This climb helped to establish Mount Hood as one of the premier hiking and mountaineering destinations in the Pacific Northwest.

4. In 1978, the famous Oregon Vortex was added to the National Register of Historic Places. This mysterious attraction, located near Gold Hill, Oregon, is famous for its optical illusions and strange gravitational effects, which continue to baffle visitors and scientists alike.

5. On November 28, 1917, the state of Oregon officially ratified the 19th Amendment to the US Constitution, which granted women the right to vote. This was a significant milestone in the fight for women's suffrage and helped to pave the way for greater gender equality in the United States.