WATCH: Inauguration Mass of Pope Leo XIV live from St. Peter’s Square

The Catholic Church’s papal transition is set to draw to a celebratory close on Sunday morning in Vatican City. According to Sky News, officials are expecting nearly a quarter of a million people to pack St. Peter’s Square to celebrate the papal inauguration. Millions more are expected to watch across the world.

The holy Mass for the beginning of the pontificate of Pope Leo XIV is set to begin at 10:00 a.m. local time, 4:00 a.m. ET. For those looking to follow along, the Vatican has prepared a booklet for the Mass in pdf form. The American-based Catholic television network EWTN has been broadcasting live from Rome since the death of Pope Francis hours after he was driven through St. Peter’s Square on Easter Sunday. The network is planning to carry the inaugural Mass for Pope Leo live on YouTube, which can be seen below.

Catholic News Agency has prepared a list of the key moments to look for during the celebration. Highlights include a prayer at the tomb of St. Peter, a procession led by deacons holding the signs of papal authority — the pallium, gospels, and fisherman’s ring — an “act of obedience and fidelity of the universal Church to the new pope,” and the rite of initiation of the pontiff, where the new pope will receive his pallium and ring.

Dignitaries from around the world are expected at the celebration, including a delegation from the United States led by Vice President JD Vance and Secretary of State Marco Rubio, both of whom are practicing Catholics.

As the world celebrates the first American pope, many Catholics from the United States are hopeful about what’s to come. Bill Donohue, president and CEO of the Catholic League for Religious and Civil Rights, told Blaze News, “I would like to hear Pope Leo XIV speak about the multiple challenges awaiting his pontificate. This would surely entail speaking about contemporary moral issues and addressing the problems that militant secularism has wrought.”

Donohue continued, “He does not have to lay out a specific agenda, but we need to learn of his vision for the Church and where he wants to take us.”

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