Norddeutsche Schachbund, 1868 (Hamburg)
a single #2–5 (3 pr.)
Open only to members.
1 pr. J. Berger (Motto: Vom Süd zum Nord)
2 pr. ???
3 pr. ???
No contemporary source has yet been found that combines all details: the tourney, the award, the author, the motto and the problem.
Berger's book appears to indicate that the problem was faulty when it competed, and that the correction (added white Pawn on g2) was made later.
While there is no explicit mention of it in the listed sources, it is likely that non-members could become members.
1 Prize: J. Berger
[*] = Faulty: Multiple key moves
Key: 1. Qh5
Source: Berger: Probleme, Studien und Partien (1914), pr. 56, p. 29-30 [corrected by +wPg2]