Emperor Henry, obliging the pope’s request to fight the eastern empire in Italy, sets out in 1022, down the Adriatic coast for southern Italy commanding a large force.

He sends Pilgrim, Archbishop of Cologne, ahead with a slightly smaller army along the Tyrrhenian littoral with the objective of subjugating the Principality of Capua.

A third army, smaller still, under the command of Poppo of Treffen, who Henry had in 1019 appointed Patriarch of Aquileia, goes through the Apennines to join Henry in besieging the imperial fortress of Troia.

Pilgrim does capture Pandulf IV of Capua and extract oaths of allegiance from both Capua and the Principality of Salerno, but all three divisions fail to take Troia from Boioannes.

Henry nearly executes the treacherous prince of Capua, but relents at the last moment at Pilgrim's pleading and instead sends him off to Germany in chains and appoints Pandulf of Teano to replace him as prince.

Though his main objective had been missed, Henry leaves the south in the knowledge that western imperial authority still extends that far.

On his return journey, he attends a synod at Pavia, where he advocates Church reform.