LOUIS IV. (or V), "the Bavarian," German king and Roman emperor, was born in 1286. He was the son of the duke of Bavaria, and in 1314, after the death of the emperor Henry VII., was elected to the throne by five of the electors, the others giving their votes for Frederick, duke of Austria. This double election led to a civil war, in which Frederick was supported by the church and by many nobles, while the inhabitants of the great cities rallied round Louis. In 1322 Louis gained the battle of Miihldorf, taking Frederick prisoner; but the war still went on. Pope John XXII. excommunicated Louis in 1324 ; whereupon, wishing to bring the conflict to an end, Louis offered to liberate Frederick on condition that he would withdraw his claim to the throne, and restore the cities and imperial lands seized by his party in Swabia. Frederick, finding that the obstinacy of his brother, Duke Leopold, would render it impossible to fulfil these terms, returned to cap-tivity ; and Louis was so touched by his magnanimity that he proposed that they should share the responsibilities of government. The plan was tried but did not succeed, and was virtually abandoned before Frederick's death in 1330. In 1327 Louis had gone to defend his rights in Italy, where he was crowned emperor by Pope Nicholas V., whom he supported in opposition to Pope John XXII. Beturning to Germany in the year of Frederick's death, he made peace with the house of Austria, but John XXII. refused to be conciliated, and his successor Benedict XII., acting in part under the influence of France, continued the struggle. Irritated by the revival of papal pretensions which no longer commanded respect in Germany, the electors met at Rhense, and on the 15th of July 1338, issued an important declaration to the effect that the emperor derived his right to the German and imperial crowns, not from the pope, but from the electors by whom he was appointed. As the representative of national independence, Louis might have made himself one of the most popular of the emperors, but he excited bitter jealousies by his grasping and unscrupulous disposition. By his marriage with Margaret, the sister of Count William of Holland, he secured Holland, Zealand, Friesland, and Hainault ; and he obtained the mastery of Tyrol by separating the heiress, Margaret Maultasch, from her husband, a son of John, the powerful king of Bohemia, and making her the wife of his own son Louis, to whom (in 1322) he had granted the march of Brandenburg. The enemies he thus created were reinforced by Pope Clement VI., who not only excommunicated him again, but (in 1346) persuaded a party of the electors to appoint a new king. Their choice fell on Charles, margrave of Moravia, the son of King John of Bohemia, who at once made an unsuccessful attempt to recover Tyrol. The outbreak of a new civil war was prevented by the sudden death of Louis at a bear hunt near Munich, on the 11th of October 1347. The conflict between the papacy and the empire was practically closed during the reign of Louis, and he marked an epoch by his encouragement of the cities in opposition to the princes and nobles.

See Mannert, Kaiser Ludwig IV., 1812 ; Fr. von Weech, Kaiser Ludwig der Baier und Konig Johann von B'ohmen, 1860 ; and Dôbner, Die Auseinandersetzung zwischen Ludwig IV. dem Baier und Friedrich dem Schbnen von Oesterreich, 1875.