Jonathan Sarfati: The meticulous Edward Winter gives the date as 1850 http://www.chesshistory.com/winter/... . The same game score was later attributed to the future Pope Leo XIII who all the same was a keen chessplayer -- see Guila vs G Pecci, 18753705. Popes (C.N.s 3696 & 3701)
Peter Anderberg (Harmstorf, Germany) reports that the game allegedly played by the future Pope Leo XIII in the mid-1870s was in fact published in the Deutsche Schachzeitung, May 1850, page 175, as having occurred between Shumov and von Jaenisch: 1 e4 e5 2 
f3 c6 3 
c4 c5 4 c3 f6 5 d4 exd4 6 e5 d5 7 exf6 dxc4 8 
e2+ e6 9 fxg7 
g8 10 cxd4 xd4 11 xd4 xd4 12 h5 f6 13 O-O xg7 14 b5+ c6 15 xb7 xg2+ 16 
xg2 g6+ 17 h1 d5+ 18 f3 xf3+ 19 xf3 g1 mate.
When was the game first associated with the name of Pope Leo XIII?"
Winter continues:
3721. Popes (C.N. 3696, 3701 & 3705)
David R. Sands notes in the Washington Times of 23 April 2005 that we have cast some doubt on the authenticity of the game ascribed to Pope Leo XIII, but he also points out that Francis J. Wellmuth gave various specifics when including it in The Golden Treasury of Chess (New York and Philadelphia, 1943). We quote below Wellmuth’s exact words, from page 63 of the book (and page 47 of a subsequent paperback edition):
‘Played in Perugia, about 1875. The following game, played by Joachim Cardinal Pecci (afterwards Pope Leo XIII) was obtained during my visit at Vatican city in 1925-26, from my old colleague Rev. Maurice de la Taille, S.J., Professor of professors at the Gregorian University, Rome Italy, and author of Mysterium Fidie [sic – Fidei] – F.J.W.’
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