K.T., thank you much for the information!
The works of Joe Phillips are usually easy to recognize, but this particular picture was a puzzle for me. Well, then we should usk Joe for a licence.
The other suggestions sound nice as well, here the pics I have found on these people:
Karl Heinrich Ulrichs;
Harvey Milk
Fanny Ann Eddy;
Pierre Seel
Harry Hay;
Larry Kramer
Oscar Wilde;
Lytton Strachey
E. M. Forster;
Yukio Mishima
Edmund White;
Rainer Werner Fassbinder
Pierre Paolo Pasolini
Dag Hammarskjöld;
John Maynard Keynes
The last 2 gentlemen were not openly gay, I suppose? I have found some indices that Mr. Keynes was homosexual in his youth, but no further informations for Mr. Hammarskjöld. Can you help me out with a link? Thanks a lot!