1907 —Sir Fredrick Hopkins determines that certain organic substances (later named vitamins) are essential for good health and that certain amino acids, also essential to health, are only supplied through one’s diet.

• The Palmer-Gregory School is founded in Oklahoma City.
• Oklahoma, formerly Oklahoma and Indian Territories, becomes the 46th state on November 16. Congress refuses to allow the state to be named Sequoyah, the Indian creator of the Cherokee alphabet.
• A Gentlemen’s Agreement with Japan is drafted in which Japan recognizes the right of the United States to refuse Japanese laborers entry into the country (February 24).
• Alabama and Georgia adopt state prohibition laws.
• Mother’s Day is observed for the first time in Philadelphia through the efforts of Anna M. Jarvis, who arranges a special church service.
• The Lusitania, one of the world’s largest steamships, sails to New York City on its maiden voyage. It sets a speed record of five days, 54 minutes from Queenstown, Ireland.