Henry Frederick, Hereditary Prince of the Palatinate

Henry Frederick, Electoral Prince of the Palatinate, (German: Heinrich Friedrich; 1 January 1614 – 7 January 1629 in the Netherlands) was the eldest son of Frederick V, the Winter King, and his wife, Elizabeth Stuart, daughter of King James VI of Scotland and I of England.

As soon as the prince was born, Elizabeth ordered "pieces" using the English word, meaning the firing of cannon to celebrate the birth.He was most probably named after his late uncle Henry Frederick, Prince of Wales, who, like Henry Frederick, died a teenager.

He wrote a letter to his grandfather King James from The Hague on 11 May 1621.

Henry Frederick drowned at the age of 15. He was on his way to Amsterdam to see the captured Spanish treasure fleet there and drowned crossing the Haarlemmermeer.