1. Delaware became the first state to ratify the United States Constitution on October 3, 1787. The state's delegation to the Constitutional Convention, led by John Dickinson, overwhelmingly voted in favor of the document, paving the way for its eventual adoption by other states.

2. On October 3, 1847, the Delaware College (now known as the University of Delaware) opened its doors to its first class of students. The college was established by the state's General Assembly in 1833 and was the first institution of higher learning in Delaware.

3. Delaware's official state seal was adopted on October 3, 1847, the same day that the Delaware College opened. The seal features the state's coat of arms, which includes a shield with a plow, a ship, and an ear of corn, symbolizing the state's agricultural and maritime heritage.

4. In 1950, Delaware inaugurated its first female governor, Elbert N. Carvel, on October 3. Carvel had previously served as the state's lieutenant governor and was elected to the top office in 1948, becoming one of only a handful of women to serve as governor in the United States at that time.

5. On October 3, 1993, the Delaware-based Dupont company celebrated its 200th anniversary. Founded in 1793 by French émigré Éleuthère Irénée du Pont, the company has played a significant role in the state's economy and history, particularly in the development of the chemical industry.