He was the third (and youngest surviving) son of Albert III, Duke of Saxony, and Sidonie of Poděbrady, daughter of George of Podebrady.

Born prematurely seven months after his immediate elder sibling in Torgau, Frederick was a member of the Albertine line, the junior branch of the prestigious House of Wettin which ruled Saxony.

The Order's fortunes had declined throughout the 15th century, and they hoped that selecting someone connected by marriage to the ruling Jagiellon dynasty of Poland would strengthen their position.

When John I Albert summoned Frederick to do homage for the Order's holdings, he referred the matter to the Imperial Reichstag.

The Reichstag informed John I Albert that he could not interfere in the Grand Master's free exercise of power in Prussia.