On December 28th:

 1694  Queen Mary II of England Dies

On December 28th, 1694, Queen Mary II of England, who had jointly ruled with her husband William III, passed away. Her reign saw significant developments, including the Glorious Revolution and the establishment of constitutional monarchy.

 1846  Iowa Becomes the 29th U.S. State

A new star joined the constellation of states on December 28th, 1846, as Iowa was admitted to the Union. Known for its agricultural contributions, Iowa became the 29th state of the United States.

1973  The Endangered Species Act is Signed into Law

On this day in 1973, President Richard Nixon signed the Endangered Species Act into law, aiming to protect and conserve threatened and endangered species and their habitats in the United States.