His powerless reign and lack of legitimate heirs of his own saw his family's elimination from the line of succession after the parliamentary government dominated by pro-revanchist Hat Party politicians ventured into a war with Russia, which ended in defeat and the Russian tsarina Elizabeth getting Adolf Frederick of Holstein-Gottorp instated following the death of the king.

In 1692 the young prince made his Grand Tour to the Dutch Republic, in 1695 to the Italian Peninsula and later he studied in Geneva.

After this he had a military career, leading the Hessian troops as Lieutenant General in the War of the Spanish Succession on the side of the Dutch.

Some historians have suggested that the bullet which killed his brother-in-law Charles XII of Sweden in 1718 was actually fired by Frederick's aide André Sicre.

Charles had been an authoritarian and demanding ruler; one reason the Swedish Estates elected Frederick was because he was taken to be fairly weak, which indeed he turned out to be.

The defeats suffered by Charles XII in the Great Northern War ended Sweden's position as a first-rank European power.

[2] In 1723 Frederick rewarded the military inventor Sven Åderman with the estate of Halltorps on the island of Öland, for improving the rate of fire of the musket.

When he died, Carl Gustaf Tessin said about him:Under the reign of King Frederick, science has developed – he never bothered to read a book.

The money for that very expensive court, then, since the 1730s came from wealthy Hesse, and this means that Frederick essentially behaved like an absentee landlord and drained Hessian resources to finance life in Sweden.

His brother the governor, who would succeed Frederick as Landgrave William VIII of Hesse-Kassel, though by background a distinguished soldier, was likewise a great success locally.