Reinhard Keiser, German composer (died 1739)

Reinhard Keiser was a German opera composer based in Hamburg. He wrote over a hundred operas. Johann Adolf Scheibe considered him an equal to Johann Kuhnau, George Frideric Handel and Georg Philipp Telemann, but his work was largely forgotten for many decades.

January 9 is the ninth day of the year in the Gregorian calendar; 356 days remain until the end of the year.