Donegan was born at Cordella, the family home of his parents Horace George Donegani and Emma (Pembroke) Hand in Matlock Bath, Derbyshire.

He once proposed a reduction of the period of Lent from forty to seven days, for "what was acceptable in the seventeenth century has become unrealistic for men and women catching commuter trains.

In December 1955, Donegan sponsored an apartment near the Cathedral of St. John the Divine for a family of German refugees, helping the husband find work as well.

"[5] In 1965, several parishioners in the Diocese of New York, upset by their Bishop's activism in the civil rights movement, withdrew pledges of $2 million for the completion of St. John the Divine.

In response, Donegan said, "I can only hope that the Cathedral's very unfinished quality will stand as a memorial to a diocese which in the twentieth century tried to do what it believed to be right."

He stated, "Were it in my power, I would fine every person who did not vote, and reward doubly everyone who enlisted in the service of our country, whether as an Episcopalian in the armed forces or as Quaker in the courageous group who will carry the wounded off the field of battle."

Should there be a presentment and trial of Bishop Pike (which I hope and pray will not happen) the harm, the divisiveness and the lasting bitterness that will be inflicted on the Church we love and serve will be inevitable."

In 1967 he made the stunning announcement that he would be taking the donations for finishing St. John the Divine and put them toward housing and development projects in nearby Harlem.

He once said of St. John, "This unfinished cathedral, towering as it does over this great and suffering metropolis, shall be the prophetic symbol that our society is still as rough-hewn, ragged, broken and incomplete as the building itself."