One of the things that happened that year was the death of Arnold Schoenberg, which is why I have always wondered, if there is anything to this metempsychosis thing, if I might be the reincarnation of Mr. Schoenberg. Maybe not.
But there was a lot more happening that year, including the piece I just put up on another post, the Symphony No. 1 of Henri Dutilleux, a quite lovely piece. I'm just starting to explore the music of Dutilleux, so there will be more posts on him.
1951 was the year that Karlheinz Stockhausen started composing in his characteristic style (pieces prior to this date were more student efforts). Kreuzspiel dates from 1951.
Another piece, begun in 1951 but completed in 1952, was Structures I for two pianos by Pierre Boulez:
It was in 1951 that John Cage started writing music using chance procedures. The Music of Changes for piano, dates from that year:
1951 comes in the middle of one of the darkest phases of the life and career of Dmitri Shostakovich. Between the second denunciation of his work, in 1948, and the death of Stalin in 1953, he was unable to premiere his most important works such as the Violin Concerto No. 1. In 1950, however, he was on the jury of the First International Bach Competition in Leipzig (celebrating the 200th anniversary of Bach's death) and hearing so very many preludes and fugues inspired him to write a complete set in all the keys. He finished the last one, in D minor, in February 1951:
Alas, there does not seem to be a piece from Messiaen dating from 1951. His Quatre études de rhythme come just before and the first of his pieces inspired by birdsong, just after. Here is Le merle noir from 1952:
The last work of Stravinsky's neo-classical period, The Rake's Progress, was composed in 1951:
The premiere recording of Duke Ellington's Harlem (commissioned by Toscanini!) was released in 1951:
Elliot Carter's String Quartet No. 1, the fruits of a long stay isolated in the Arizona desert, was completed in 1951:
I could go on, but I think that this certainly gives you a sense of the year (other than pop music where Perry Como, Mario Lanza and Tony Bennett--who is still recording!--reigned). Some of the information I got from this useful site: 1951 in music.