[3] After Henry's victory against the Saxons, he arranged for an assembly at Goslar on Christmas Day 1075 to swear an oath recognising Conrad as his successor.

[5] He did appoint Albert III of Namur, the deceased duke's brother-in-law, as his son's vice-duke (vicedux) to perform the daily functions of government.

[5] He was placed in the care of Archbishop Tedald of Milan and Bishop Denis of Piacenza, both excommunicated prelates and opponents of Pope Gregory VII.

[11] In October 1080, Conrad was present in the camp when a force from northern Italy defeated the troops of Marchioness Matilda of Tuscany near Mantua.

[5] In December 1080, the Saxon lords who had supported the kingship of the late Rudolf of Swabia against Henry gathered "to discuss the state of their kingdom [Saxony]" in Bruno of Merseburg's words.

[16] In 1093, with the support of Matilda and her husband, Welf V, along with the Patarene-minded cities of northern Italy (Cremona, Lodi, Milan and Piacenza), Conrad rebelled against his father.

[20] Ekkehard otherwise gives positive account of Conrad's motivation, describing him as "a thoroughly catholic man, most devoted to the apostolic see, inclining to religion rather than government or war ... well enough furnished with courage and boldness [yet] preferr[ing] to occupy his time with reading rather than with sports".

[19] In mid-March Conrad was captured by his father through a ruse, but soon escaped and in late July was elected king by Matilda, Welf and their allies and crowned in Milan by Archbishop Anselm III.

[22] The accusation might have been that Arnulf had performed undue service to Conrad to secure his investiture, or that he had been too obeisant, a charge of simony ab obsequio.

[23] Conrad was at the height of his power in 1094, when his father was staying with Margrave Henry and Patriarch Udalric in the March of Verona, unable to enter Italy.

[24] His antipope, Clement III, elected at the Synod of Brixen in 1080, who was travelling with him, even offered to resign so that Henry could negotiate with Pope Urban II if that was all that stood in the way.

[25] On 15 April, in a second meeting at Cremona, Conrad swore an oath, either of "security" or of "fealty", to the pope, guaranteeing the "life, limb and Roman papacy" to Urban.

In a sign of the turning tide, Welf, with the help of Patriarch Udalric and Duke Henry of Carinthia, invaded Italy and secured his claims to the inheritance.

He once rhetorically asked Liutprand, one of the leaders of the Pataria, "Since you are a teacher of Patarenes, what do you think of bishops and priests who possess royal rights and present not food to the king?

The historian Landulf Junior praised Conrad for refusing investiture to neither Arimanno da Gavardo, the bishop-elect of Brescia, nor to Anselm IV.

[32] In April[33] or May 1098 at an assembly held in Mainz, Conrad's father had him formally deposed and his younger brother, Henry V, elected in his place.