Conrad I of Wittelsbach (German: Konrad I. von Wittelsbach) (c. 1120/5 - 25 October 1200) was the Archbishop of Mainz from 1161 until 1165, and again from 1183 until 1200, the Archbishop of Salzburg from 1177 until 1183, and the Bishop of Sabina from 1163 until 1200.

Conrad was born to the Count Palatine Otto V of Bavaria. He was educated in Paris and Salzburg. In 1160 both Christian of Buch and Rudolph of Zähringen were elected the archbishop of Mainz. To resolve the Mainzer Schism, the Council of Lodi convened by the Emperor Frederick I Barbarossa and Antipope Victor IV declared both anti-bishops and deposed, and Conrad the new archbishop. Conrad warned Raynald of Dassel, the Archbishop of Cologne, against conflict with Pope Alexander III.

In 1165 he renounced his oath of fealty to Frederick Barbarossa and fled to France which accepted him with much confusion. Therefore Frederick Barbarossa elevated Christian of Buch again the archbishop of Mainz which was recognised by the princes of the empire, but Pope Alexander III instead recognised Conrad as rightful archbishop and rewarded him with the title "Cardinal Bishop of Sabina". He escaped capture by the Imperial army in the conquest of Rome in 1165. In 1176 Alexander III and his allies inflicted a heavy defeat on the emperor, and at the ensuing Peace of Venice he recognised Christian of Buch as rightful archbishop. However Conrad was compensated with the Archbishopric of Salzburg.

After Christian's death in 1183 he renounced Salzburg and returned to Mainz as archbishop there. Conrad rebuilt the cathedral and the city fortifications which Frederick Barbarossa had destroyed following the murder of Arnold of Selenhofen in 1160. In 1184 he held one of the largest celebration parties of the Middle Ages in Germany. In autumn of 1188 he announced his intentions of leading an army on Crusade, which he set in motion for 1197. When Frederick Barbarossa died in 1197, Conrad with the other electors chose his two year-old son as the next emperor. In the controversy of the succession of the Principality of Antioch, Conrad joined with the patriarchs in support of Raymond-Roupen against Bohemond, however Bohemond was declared the successor.

Conrad remained in Palestine which led to the double election of Philip of Swabia and Otto IV of Brunswick. In 1199 Pope Innocent III sent Conrad back to Germany to mediate the violent dispute, which in April 1200 led to a mild armistice. Conrad then returned to Palestine but died on the way in Hungary and was buried in Mainz Cathedral.

Preceded by:

Christian I of Buch

Succeeded by:

Christian I of Buch opposed Rudolph of Zähringen Archbishop of Mainz
1161 - 1165
Christian I of Buch
Christian I of Buch Archbishop of Mainz
1183 - 1200
Leopold II of Schönfeld opposed Siegfried II of Eppstein
Adalbert III of Bohemia Archbishop of Salzburg
1177 - 1183
Adalbert III of Bohemia
new creation Bishop of Sabina
1163 - 1200
John I Colonna