All photographs are copyright © 2015 by Geoff Rodkey except for the following, reprinted with permission:
1: United States Navy
2: United Kingdom Government
3: Ronin Rodkey
4: Ronin Rodkey
5: Ronin Rodkey
6: Ronin Rodkey
7: Ronin Rodkey
8: Ekler Vector/Shutterstock.com
9: Amanda Newman
10: Curtis Brown Photography
11: Hulton Royals Collection/Getty Images
12: antpun/Shutterstock.com
13: Elizabeth Newman-Corré
14: Erin Simon Berenson
15: Stephen Rees/Shutterstock.com
16: Currier & Ives N.Y.
17: Express Newspapers/Getty Images
18: cbpix/Shutterstock.com
19: khuruzero/Shutterstock.com
20: Vicke Andren
21: Marsan/Shutterstock.com
22: Firma V/Shutterstock.com
23: Tooykrub/Shutterstock.com
24: smuay/Shutterstock.com
25: Ekler Vector/Shutterstock.com
26: National Archives and Records Administration (USA)
27: Nina Lipkind
28: Alfred Eisenstaedt/Getty Images
29: Natalia Pushchina/Shutterstock.com
30: Mat Hayward/Shutterstock.com