Philip William was the eldest son of the Great Elector and his second wife, Princess Sophia Dorothea of Schleswig-Holstein-Sonderburg-Glücksburg.

Shortly after the birth of Philip William, he was invested with his mother's dominion of Schwedt, later, the Brandenburg-Prussian government added the lands of Wildenbruch.

After the coronation of his elder brother, Frederick, he became Prince in Prussia, Margrave of Brandenburg with the style Royal Highness.

The nomenclature "Brandenburg-Schwedt" came into use in the 19th century, posthumously, to distinguish the lords of Schwedt from the main line of the Hohenzollerns.

His half-brother, Prince Elector Friedrich III (later King Frederick I of Prussia), also gave him the proprietorship of several regiments.