Who was especially important to you? Any time period.
I think about Mozart most weeks of my life.
Neil Peart, drummer for Rush, is even more influential on my music understanding two years later.
It hit me much later than most, but John Lennon.
Tchaikovsky had an extremely brutal and tragic death. and he is a composer for whom I have immense admiration, because he has an enormous importance in the history of music, especially symphonic music and ballet.
I think about Shostakovich almost daily, he is a source of inspiration and I have paid tribute to Shostakovich several times in my own compositions by adding his musical monogram DSCH. I feel very close to his music, especially the preludes and fugues op87 and the fantastic dances for piano that I play regularly in concert
Charles Aznavour, Udo Jürgens - I grew up with their songs, and Charles Aznavour reached the age of 94, he grew really old - during his last years I sometimes wished to experience one of his concerts - but I have never had the opportunity to do so, Udo Jürgens died with 80, which is also a quite respectable age, but he seemed to be in such a good physical and mental condition, that I would have expected him to reach his middle nineties at least.
It is a really good thing we have much better possibilities to conserve voices and music today - in former times, when a singer passed away, his voice passed away with him or her, too.