1. In 1805, the Lewis and Clark Expedition reached the mouth of the Columbia River in present-day Oregon on December 23. This was a significant moment in the history of the Oregon Trail and the exploration of the American West.

2. On December 23, 1867, the city of Portland faced a massive fire that lasted for several days and destroyed much of the city's downtown area. This disaster led to the implementation of stricter fire safety measures in the state of Oregon.

3. In 1877, the Oregon State Legislature voted to allow women to practice law in the state. This made Oregon one of the first states in the country to open up the legal profession to women.

4. December 23, 1888, marked the date of the first issue of The Oregonian, which is still the largest newspaper in the state today. The paper played a significant role in the formation of the Oregon state government and continues to be influential in Oregon politics.

5. On December 23, 1986, the Eugene City Council voted to prohibit discrimination based on sexual orientation in housing, employment, and public accommodation. This was a significant step forward for LGBTQ+ rights in Oregon and was one of the first such ordinances in the country.