Rupert of Germany (German: Ruprecht III "Klem", Pfalzgraf bei Rhein) of the house of Wittelsbach (5 May 1352 – 18 May 1410), he was the son of Rupert II, Elector Palatine of the Rhine and Beatrix of Sicily. Rupert was Elector Palatine from 1398 and German King from 1400 until his death.
He was born at Amberg, and from his early years took part in the government of the Palatinate to which he succeeded on his father's death in 1398. He was one of the four electors who met at Oberlahnstein in August 1400 and declared King Wenceslaus deposed. This was followed by the election of Rupert as German king at Rhens on 21 August, and by his coronation at Cologne on 6 January 1401.
Winning some recognition in Southern Germany, he made an expedition to the Italian peninsula, where he hoped to receive the imperial crown, and to crush Gian Galeazzo Visconti, Duke of Milan. In the autumn of 1401 he crossed the Alps, but his troops, checked before Brescia, melted away, and in 1402 Rupert, too poor to continue the campaign, returned to Germany.
The news of this failure increased the disorder in Germany, but the king met with some success in his efforts to restore peace, and in October 1403 he was recognized by Pope Boniface IX. It was only the indolence of Wenceslaus that prevented his overthrow, and in 1406 he was compelled to make certain concessions. The quarrel was complicated by the papal schism, but the king was just beginning to make some headway when he died at his castle of Landskrone near Oppenheim on 18 May 1410 and was buried at Heidelberg.
He was married in Amberg on 27 June 1374 with Elisabeth of Nuremberg, daughter of Burgrave Frederick V of Nuremberg and Elisabeth of Meissen. They had the following children:
Rupert commissioned the Ruprecht building in Heidelberg castle. Today there is a Ruprecht-Karls-University in Heidelberg. He was succeeded as Count Palatine by his son Louis III.