Frederick II of Prussia was a composer. He was born on January 24, 1712 in Berlin to Frederick William I of Prussia and Sophia Dorothea of Hanover. He was a member of Prussian Academy of Sciences. He married Elisabeth Christine of Brunswick-Wolfenbüttel-Bevern. He died on August 17, 1786 in Potsdam.When you read the Wikipedia article, you will learn that he was also a philosopher, a patron of the arts, a flautist, a general and a brilliant administrator who overhauled both administrative and military processes, he elevated himself to King in Prussia and because all of this he is known as Frederick the Great.
It is fairly easy to add statements identifying all these roles to Wikidata. The problem though is that when he is to be identified as a conductor, a flautist, a philosopher, it is done by indicating him as an occupation, a profession. That is OK when you consider this to be a convention. It is also a convention that a king is a "politician" and that the period when a king rules is seen as a public held position.
The problem is very much that all these concepts are modern and are often ill-fitting. They are like a house of cards and many of these properties are best hidden because they confuse. Often terminology is used that is insulting by definition.. For instance Frederick the Great was not replaced by Frederic William II, Frederic William succeeded him.