Enzio of Sardinia

Enzo (or Enzio;c. 1218 – 14 March 1272) was an illegitimate son of the Hohenstaufen emperor Frederick II, who appointed him 'King of Sardinia' in 1238. He played a major role in the wars between Guelphs and Ghibellines in the Imperial kingdom of Italy, and was captured by his enemies in 1249. He remained imprisoned in Bologna until his death.

Enzo was a natural son of Frederick II by a certain Adelaide, possibly a member of the Swabian noble House of Urslingen and relative of Duke Conrad I of Spoleto. He was the eldest of the emperor's illegitimate sons and allegedly the favourite one. He had a pleasant personality, a strong physical resemblance to his father, and also shared his love for the arts. Enzo fought in the ongoing wars of his father with Pope Gregory IX and the Northern Italian communes of the Lombard League.

When Ubaldo Visconti died in 1238, the Doria noble family of Genoa, in order to secure the Sardinian Giudicato of Logudoro from Pisan domination, convinced the emperor to marry Enzo to Ubaldo's widow, Adelasia of Torres (d. 1255). Upon the marriage, Enzo by jure uxoris would accede to the Sardinian Giudicati of Logudoro (Torres) and Gallura, covering the northern half of the Sardinia island. He was created a knight in Cremona and granted the Sardinian royal title, last held by Barisone II of Arborea in 1164/65. Enzo travelled to the island to marry Adelasia in October that year.

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