Muzio Clementi was a contemporary of Mozart, but was lucky enough to live much longer. He was born in Rome and spent most of his career in London. Besides being a prolific composer & popular performer, he was a teacher, publisher and instrument maker.
Apparently when he was in Vienna in 1781 the emperor decided to stage a piano duel, as it were, between Clementi & Mozart. They both did so well the contest was declared a draw.
There’s a little story behind the choice of tunes so far included here.