1. On September 5, 1850, the United States government signed the Donation Land Claim Act into law, granting 320 acres of land to every married couple and 160 acres to single individuals who both were over 18 years old and had lived in Oregon for at least four years. This act opened up vast tracts of land in Oregon for settlement and led to a population boom in the state.

2. September 5, 1871, marked the opening of the first Oregon State Fair in Salem. Started as a small agricultural exhibition, the State Fair has grown into a major event that attracts thousands of visitors every year. In addition to agricultural displays, the fair now features carnival rides, concerts, and other entertainment.

3. On September 5, 1907, the first Rose Festival was held in Portland. The festival was created to promote the city and celebrate its many parks and gardens, especially the famous International Rose Test Garden. The Rose Festival has become an annual tradition in Portland, featuring parades, concerts, and other events for over a century.

4. September 5, 1918, was a dark day in Oregon history, as the state recorded the highest death toll from the Spanish flu pandemic. Over 800 people in Oregon died from the flu on that day alone, part of a larger outbreak that killed tens of millions of people worldwide.

5. Finally, on September 5, 1962, Oregon became the first state in the nation to legalize physician-assisted suicide. The state's Death with Dignity Act, passed in 1997, allows terminally ill patients to obtain a lethal prescription to end their lives. The law has been controversial, but has also served as a model for similar laws in other states.