I have to think I may eventually be doing a "Hats Off, Part II" since researching hats and all things millinery seems potentially infinite. I so enjoyed putting together this post that I had to force myself to stop for fear I'd segue into a fashion glossary rather than a compilation of photographs.
Norman Parkinson (whose photographs of Philip Treacy's millinery and haute couture became a collaboration and art unto itself).
Norman Parkinson
Leombruno-Bodi (1960)
Frank Horvat (1960s)
Henri Cartier-Bresson
Cindy Sherman (1978)
Fernand Fonssgrives
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F. C. Gundlach
Jacques Henri Lartigue (of his muse, Renée Perle, 1930)
Richard Avedon (of Mila Jovovich in Yohji Yamamoto)
Photographer Unknown (of President Coolidge, Mrs. Coolidge and Senator Curtis, 1925)
Alistair Grant (of Queen Elizabeth, 2009)
Richard Pohle
Robert Frank
Garry Winogrand (1950s)
Weegee, Hats in Poolroom, Mulberry Street, NYC, 1943
Loomis Dean
Robert Frank
Walker Evans (of Lincoln Kirstein, 1930)
Frank Horvat (for Givenchy, 1957)
Glen E. Friedman (of Run DMC)
Photographer Unknown (of David and Victoria Beckham)
Max Vadukul (of Rachel Weiss)
Regina Relang
Photographer Unknown
Photographer Unknown / Credit: Life Magazine (of Princess Diana)
Photographer Unknown
Photographer Unknown (at the horse races, 1920)
Photographer Unknown (1940; credit: The Luton News)
Arthur Tress (1978)
Photographer Unknown (of serviceman on Veteran's Day)
Chip Somodevilla (at the Republican National Convention, 2008)
Pete Souza (of President Ronald Reagan)
Pete Souza (of President Barack Obama 2009)
Robert Frank (1954)
Photographer Unknown (1898)
Pierre & Gilles
Cindy Sherman
John Rawlings
Henry Clark (1954)
Henry Clark (1954)
Rodney Smith
Charles C. Ebbets (1932)
Cecil Beaton
Chris Gulker
Margaret Bourke-White (of a Hindu man, 1946)
Margaret Bourke-White (of a Georgian peasant worker, 1941)
Louise Dahl-Wolfe (1963)
John Rawlings