While still a subdeacon, he was sent as a papal legate to France by Pope Alexander III in 1178, to summon the French bishops to a general council which met in Rome in March 1179.
[9] He was also appointed to obtain the oath of fealty of Conrad of Spoleto, and that of Markward von Annweiler, the Margrave of Ancona and Count of the Abruzzo, both loyal followers of King Henry.
In the latter case, following the death of Henry VI in September 1197 and of the empress Constance in December 1198, Markward swore his feudal oath before Cardinal Cinzio Cenci of San Lorenzo in Lucina and Giovanni di San Paolo of Santa Prisca, but he violated it almost immediately and brought devastation on nearly the whole of the March of Ancona.
When he and many of his followers were excommunicated by Innocent III, he sought pardon and absolution, and appeared personally before a commission of cardinals, Bishop Ottaviano of Ostia, Guido Papareschi of Santa Maria Transtiberim, and Ugolino dei Conti di Segni of San Eustachio, who absolved him and received his oath again.
In July 1200, Cardinal Ottaviano was appointed papal legate of Pope Innocent III to Philip II, King of France.
[14] Philip's resolution to follow the legate's instruction lasted only a short time, and his rejection of Ingeborg continued until her death.
[19] In July 1201, Pope Innocent was still instructing Ottaviano to restore Ingeborg, get rid of the concubine, and get Philip to pay his promised subsidy for the Holy Land.
He sat on an investigating committee of cardinals, which pronounced on the case of the archdeacon of Verona; their judgment was confirmed by Pope Innocent III on 10 May 1202.