What marked the significance of the year 1956 for Eugene O'Neill's "Long Day's Journey Into Night"?

The significance of the year 1956 for Eugene O'Neill's "Long Day's Journey Into Night" centers around its publication. This play, which is often considered one of O'Neill's masterpieces, was written earlier, during the late 1940s, but remained unpublished and unperformed during his lifetime due to his wishes for it to be released posthumously. It wasn't until 1956 that the play was published, making it accessible to the public and leading to its subsequent performances. This publication marked a critical moment in American theater history, allowing audiences to appreciate O'Neill’s exploration of personal and family dynamics, as well as themes of addiction, illness, and despair that resonate throughout the narrative.

The other options do not hold true in this context. The play was not performed for the first time in 1956, as it had its world premiere in 1956, but many people may mistake publication for performance. O'Neill had already won the Nobel Prize for Literature in 1936, so 1956 does not mark a significant anniversary related to that achievement. Additionally, while the world premiere did occur in 1956, the key factor that highlighted the importance of this year was its publication rather than its performance