The Bavarian Louis IV, emperor of Germany, born about 1285, died near Furstenfeld, in the neighborhood of Munich, Oct. 11, 1347. He was the son of Louis the Severe, duke of Bavaria, and of Matilda, daughter of the emperor Rudolph I. of Hapsburg; and after the death of his father, having been for some years under the tutelage of his mother, he became co-regent with his elder brother Rudolph in their hereditary possessions. After the sudden death of the emperor Henry VII. of Luxemburg in Italy (1313), he was chosen as his successor in October, 1314, by the majority of the electors, while his late friend Frederick the Fair of Austria, like himself a grandson of Rudolph of Hapsburg, and son of the emperor Albert I., was proclaimed emperor by the minority, under the name of Frederick III. A long war between the two rivals ensued, which, after the devastation of a large part of Germany, was terminated by the battle of Ampfing or of Muhldorf, Sept. 28, 1322, which made Frederick the captive of Louis. His election was annulled by Pope John XXII., who in 1323 ordered him to abdicate, and on March 21, 1324, he was excommunicated.

The same year he married Margaret of Holland. He was summoned to appear before the pope, July 11, but the diet of Ratisbon declared the citation null; and in 1325 he concluded a treaty with Frederick, releasing him from captivity on condition that he would return if he should prove unable to persuade his adherents to acknowledge the imperial title of the victor. Not succeeding in this object, Frederick kept his promise, and Louis not only renewed his early friendship with him, but made him governor of his hereditary possessions in Bavaria. In 1327 he declared the pope a heretic, started for Italy, and was crowned in Milan, and on Jan. 17, 1328, in Rome, by the bishops of Venice and Aleria. He deposed Pope John, and procured the election of Peter de Corbi-ere, who took the title of Nicholas V. But this step caused a general movement against the emperor in Italy, which compelled him speedily to retire from Rome. John XXII. not only maintained himself, but he as well as his successors Benedict XII. and Clement VI. continually endangered the position of the emperor by raising up foreign enemies and rivals in Germany. Of the latter, Charles of Bohemia was in 1346 elected emperor.

Louis, however, having strengthened his power in Germany by patronage bestowed on his son Louis, as well as by the inheritance of Holland, Zealand, Friesland, and other possessions through his wife Margaret of Holland, was enabled in 1347 to prepare for another expedition to Italy, when he suddenly died while hunting, of apoplexy, or, as some believed, of poison. Charles succeeded him as the fourth of that name.