Return to the Continent (1307–28)
In 1307, on Edward's death, Otto left England permanently. He remained in the service of the crown for a while longer, however, for until 1317 he represented England at the Papal Curia. He was a benefactor of Vale Royal, an Edwardian foundation. The chronicler of Vale Royal described Grandson in these terms:
"Now there was at that time with the King a good and holy man, and a most strenuous knight in arms, named Otto de Grandison, whose memory be blessed for ever."
He founded a Franciscan friary in 1289 and a Carthusian monastery at La Lance in 1317.
At the end of his life he returned to Grandson, which he had inherited from his father and to which he had made recurrent visits throughout his adult life. He never married and was succeeded by his nephew. He had advanced many of his relatives through his embassies, especially in the church. Three of his relatives served as Bishops of Lausanne and another nephew, John Grandisson, succeeded to the Diocese of Exeter. In the spring of 1328, the ninety-year-old knight set out tor one last trip to Rome. Close to Aigle, he was taken ill. On 5 April 1328, he died.
A vidimus (attested copy) of his last will and testament gave details of his funeral wishes.
"I choose burial in the cathedral church of B[lessed]. Mary [Lausanne]. Also I will and order
that when my body shall be carried to the church to be laid thereupon, two men armed with my arms, and each carrying my banner with the same arms, shall precede my body on two horses, each of which shall be worth 100 livres Lausanneois, and let one of the horses be covered with my arms and the other with iron [carapace], and let the said horses be offered [with] the aforesaid arms and coverings to the aforesaid church of Lausanne, who as rightful ambassadors shall remain for the remission of my sins. . . I give and bequeath to the church of Lausanne all my ornaments, clothing and silverware which are now deposited there, with the exception of a small gold cross and a statue of the B[lessed]. Mary."
His nephew Pierre II de Grandson succeeded him as the Lord of Grandson.