Warren G. Harding was the 29th President of the United States, serving from 1921 to 1923. He was born in 1865 as Warren Gamaliel Harding and was later known as Herbert Warren. His middle name was changed to Herbert in honor of his mother's maiden name. He was a Republican and was known for his 'return to normalcy' after World War I. His nickname was 'CAL', which stands for 'Calvin Coolidge Jr.', his running mate in the 1920 election.