Otto II (c. 995 – 7 September 1047), a member of theEzzonid dynasty, wasCount Palatine of Lotharingia from 1034 until 1045 andDuke of Swabia from 1045 until his death.

Otto was the son of theLotharingian count palatineEzzo (955–1034) and his wifeMatilda (979–1025),^[1] a daughter of EmperorOtto II and his consortTheophanu.^[2] He was a member of theEzzonian dynasty. Otto's elder brotherHerman becameArchbishop of Cologne in 1036; his sisterRicheza married thePolish kingMieszko II Lambert in 1013.

Upon the death of his father in 1034, Otto succeeded him as count palatine as well as count inDeutz and in the RhenishAuelgau, as his elder brotherLiudolf had died already in 1031. He also served as protector (Vogt) ofBrauweiler Abbey nearCologne, which had been founded by his parents.

In the conflict with DukeGodfrey III of Lower Lorraine, Otto remained a loyal supporter of theSalian kingHenry III. In turn Henry vested him with the princelessDuchy of Swabia, which he had seized upon the early death of DukeHerman IV. At Easter on 7 April 1045 inGoslar, the ducal title was awarded to Otto; in exchange, he gave up the office of count palatine, which was bestowed on his cousinHenry I. Also, his territories inKaiserswerth andDuisburg devolved onto the crown.

Otto married a daughter of CountHugh IV of Nordgau. He had a daughter,Richenza (c. 1025 – 1083), who married, firstly, Herman, Count ofWerl,^[3] and, secondly,Otto of Nordheim.^[4] Another daughter,Hildegard of Egisheim, marriedFrederick of Büren, and they were the parents of DukeFrederick I of Swabia.^[5] Recently, any matrimonial alliance of Otto has been disputed.

On 7 September 1047, Otto died unexpectedly at his castle,^[6] theTomburg, while preparing an imperial campaign against the invading forces of CountBaldwin V of Flanders and CountDirk IV of Holland. He was buried in Brauweiler Abbey; the ceremony was held by his brother-in-law, Bishop Bruno of Toul, the laterPope Leo IX. In 1048, Emperor Henry III appointedOtto of Schweinfurt his successor as Duke of Swabia.

• Commire, Anne; Klezmer, Deborah, eds. (2000).Women in World History: A Biographical Encyclopedia. Yorkin Publications.
• Robinson, I. S. (1999).Henry IV of Germany 1056-1106. Cambridge University Press.
• Robinson, I.S. (2008).Eleventh-century Germany: The Swabian chronicles. Manchester University Press.
• Robinson, I.S. (2015).The annals of Lampert of Hersfeld. Manchester University Press.
• Wilson, Peter H. (2016).Heart of Europe. Harvard University Press.

• 1047 deaths
• Dukes of Swabia
• Counts Palatine of Lotharingia
• People of Byzantine descent
• 11th-century German nobility
• Burials at Brauweiler Abbey

• Articles with short description
• Short description is different from Wikidata
• Year of birth unknown