Conversation so far:
When was the Abbey founded by Augusta, Lady Gregory?
On 11 May 1904, the society formally accepted Horniman's offer of the use of the building.
What was significant about the society with Augusta, Lady Gregory formally accepting Horniman's offer of the use of the buildling?
As Horniman was not normally resident in Ireland, the Royal Letters Patent required were paid for by her but granted in the name of Lady Gregory.
What was the Abbey with Augusta, Lady Gregory's first production?
One of her own plays, Spreading the News, was performed on the opening night, 27 December 1904.
Was Augusta, Lady Gregory's play Spreading the News successful on the Abbey's opening night?
Spreading the News was very successful and it is still acted at the Abbey Theatre as late as 1961.
What other works did Augusta, Lady Gregory put on at the Abbey?
Synge's The Playboy of the Western World

Question: What was the most successful production they did?
Self-contained rewrite: What was the most successful production Augusta, Lady Gregory did at the Abbey?