Otto was born in the
Austrian capital,
Vienna, the youngest son of King
Albert I of Germany and
Elizabeth of Carinthia, a member of the
House of Gorizia-Tyrol (
Meinhardiner). His elder brothers were
Rudolf III, who became
King of Bohemia in 1306,
Frederick the Fair, elected
King of the Romans in opposition to
Louis the Bavarian in 1314, the Austrian dukes
Leopold I and
Albert II, as well as
Henry the Friendly. After the murder of King Albert I in 1308, the Habsburgs lost out in the struggle for the
German throne, when Frederick the Fair was defeated by his
Wittelsbach rival
Louis in the 1322
Battle of Mühldorf. In the course of a rapprochement of both dynasties, Otto married Elizabeth of Wittelsbach, a daughter of Duke
Stephen I of Bavaria. In 1327 he founded
Neuberg Abbey in Styria, on the occasion of the birth of his first son Frederick II, and the Chapel of Saint George in the
Augustinian Church in Vienna. When his wife Elizabeth died in 1330, she was buried at the Neuberg Abbey church. From 1329 onwards, Otto administered the original Habsburg possessions in
Swabia (
Further Austria). In 1330, he and his brother Albert II were enfeoffed with the Austrian duchy. Louis IV,
Holy Roman Emperor since 1328, also vested Otto with the title of an
Imperial vicar. In February he developed close ties with the mighty
House of Luxembourg by secondly marrying
Anna of Bohemia, daughter of King
John the Blind and sister of future emperor
Charles IV, in the
Moravian royal city of
Znojmo. Two months later, Otto's maternal uncle, the
Meinhardiner duke
Henry of Carinthia, died without male heirs, whereupon Emperor Louis IV on 2 May 1335 ceded the Duchy of Carinthia, the adjacent
March of Carniola and the southern part of the
Tyrol to Otto and Albert as Imperial fiefs in
Linz. Otto was enthroned as duke in accordance with the archaic
Carantanian rite on the
Zollfeld plain, and, from that time onwards, took care of Carinthia rather than of the Austrian duchy. In 1337 he founded the
knightly order Societas Templois for the
crusade against the pagan
Prussian and
Lithuanian tribes. His nickname "the Merry" refers to the festive atmosphere at his court. Otto died at Neuberg Abbey at the age of 37. His sons and titular successors Frederick II and
Leopold II died shortly afterwards in 1344 (presumably poisoned), and the line became extinct. ==Marriages and children==