Katharine Susan Anthony (Sometimes also spelled Katherine) (27 November 1877 Roseville, Logan County, Arkansas - 20 November 1965 New York City) was an US biographer best known for "The Lambs" (1945), a controversial study of the British writers Charles and Mary Lamb.

Katharine was born in Roseville, Logan Co, Arkansas, the third daughter of Ernest Augustus Anthony 1846-1904 and Susan Jane Cathey 1845-1917. Her father was a grocer and later a policeman.

She became a public school teacher by 1910 and worked at that time in Fort Smith, Sebastian Co, Arkansas. She moved from Arkansas perhaps because her mother had died in 1917, and by 1920 she is living in Manhattan with her life-partner Elisabeth Irwin (1880-1942), the founder of the Little Red School House.

Some of Katherine's works are:

• "Mothers Who Must Earn" 1914
• "Feminism in Germany and Scandinavia"
• "Margaret Fuller, A Psychological Biography" (1920)
• "Catherine the Great". New York: Garden City Publishing Company. 1925.
• "Queen Elizabeth" 1929
• "Louisa May Alcott" (1938)
• "First Lady of the Revolution: The Life of Mercy Otis Warren." George S MacManus Company
• "Dolly Madison, Her Life and Times" (1949)
• "Susan B. Anthony: Her Personal History and Her Era" (1954)