Henry of Almain was the song of one of the wealthiest men in Europe who joined what?
Henry of Almain Henry of Almain (Anglo-Norman French: "Henri d'Almayne") (2 November 1235 – 13 March 1271) was the son of Richard, 1st Earl of Cornwall and his first wife Isabel Marshal. His surname is derived from a vowel shift in pronunciation of "d'Allemagne" (English: of Germany), so called by the elites of England because of his father's status as the elected German King of the Romans (the "King of Almayne").
William Adelin William Ætheling (] ; 5 August 1103 – 25 November 1120), designated or titled Adelin (alternately rendered as "Adelinus", "Adelingus", "A(u)delin" or other Latinised Norman-French variants of "Ætheling"), was the son of Henry I of England by his wife Matilda of Scotland, and was thus heir apparent to the throne. His early death without issue caused a succession crisis, known in history as The Anarchy.