In 1789 he wrote the last three Quartets (K. 575, 589, and 590), dedicated to King Frederick William (1688–1740) of Prussia, a noted cellist.
In the field of the string quarter Mozart produced two important groups of works that completely overshadowed any he had written before 1780: in 1785 he published the six Quartets (K. 387, 421, 428, 458, 464, and 465) and in 1786 added the single Hoffmeister Quartet (K. 499). In 1789 he wrote the last three Quartets (K. 575, 589, and 590), dedicated to King Frederick William (1688–1740) of Prussia, a noted cellist.