Short answers, pulled from the story.
Astronomy & Astrophysics published its first issue in January 1969. The founding meetings took place in 1968, beginning with a gathering at Leiden University on the 8th of April 1968 and culminating in the first official Board of Directors meeting in Paris on the 11th of October 1968.
Five national journals merged into A&A at its launch in 1969: the Bulletin Astronomique (France, est. 1884), the Bulletin of the Astronomical Institutes of the Netherlands (est. 1921), the Journal des Observateurs (France, est. 1915), the Annales d'Astrophysique (France, est. 1938), and the Zeitschrift für Astrophysik (Germany, est. 1930). Sweden's Arkiv för Astronomi joined in 1973 and the Bulletin of the Astronomical Institutes of Czechoslovakia in 1992.
Stuart Pottasch and Jean-Louis Steinberg were appointed the first editors-in-chief of Astronomy & Astrophysics at the Brussels meeting in July 1968. They served together from the journal's first issue in 1969 through 1972.
Astronomy & Astrophysics is currently sponsored by 27 countries plus a representative of the European Southern Observatory. The membership expanded from its original European base to include non-European countries after the Board of Directors opened applications to any country with active astronomical research in 2004.
Astronomy & Astrophysics is published by EDP Sciences, which took over from Springer Science+Business Media under a new contract signed in 2001. The current editors-in-chief are Thierry Forveille and João Alves.
Since the start of 2022, Astronomy & Astrophysics has been published in full open access under the Subscribe to Open model. Before 2022, the journal operated a hybrid arrangement in which some sections were freely available immediately and others had a twelve-month embargo.