Louis IV of Bavaria of the House of Wittelsbach, born 1282, was duke of Bavaria from 1294, duke of the Palatinate from 1329 and, after 1314, Holy Roman Emperor. Louis died on October 11, 1347.

Louis was the son of Louis II, Duke of Upper Bavaria, who was married to Beatrix von Silesia-Glogau. Their children were:

• Louis V the Brandenburger, duke of Bavaria, born 1316
• Stephen II of Bavaria, duke of Bavaria, born 1317

In 1324 he married Margaret of Holland, countess of Hainaut and Holland. Their children were:

• Louis VI the Roman, duke of Bavaria, born 1330
• William V of Holland, Count of Hainaut and Holland, born 1327
• Albert of Holland, Count of Hainaut and Holland, born 1336
• Beatrix, born 1344
• Otto V the Bavarian, Duke of Bavaria, born 1346

In January 1328 he entered Rome and had himself crowned emperor by the aged senator Sciarra Colonna, called captain of the Roman people. Three months later Louis published a decree declaring "Jacque de Cahors" (Pope John XXII) deposed on grounds of heresy. He then installed a Spiritual Franciscan, Pietro Rainalducci as Antipope Nicholas V, who was deposed after Louis left Rome in early 1329.