The service was held in the nation's capital of Khartoum on Sunday.
On our way to Khartoum to be at birth of the new Province of Sudan: churches of courage and suffering, faithful to Jesus, amazing people
— Justin Welby ن (@JustinWelby) July 28, 2017
His Grace Archbishop Ezekiel Kondo will lead the province. Justin Welby called it a "joy and privilege" to preside over the ceremony and deemed it a "new beginning" for Christians in the predominantly Muslim nation.
The new province was created after the province of South Sudan, which has a predominantly Christian population, requested it.
Since the creation of South Sudan six years ago, the Sudanese Anglican church was controlled from Juba, the capital of South Sudan.
The split has been in the works since April 2016 when the Anglican Consecutive Council sent a team to Sudan to check if a new province would be pliable.
While in Sudan, Welby went to the diocese of Kadugli, where he visited refugees and met with church leaders.
He said Sudan sets an example on how to treat refugees. His aim during the trip is to encourage peace and reconciliation.
During his stay in Africa, Welby will travel to Uganda and visit two refugee camps which house around 900,000 South Sudanese refugees. He will be hosted by the primate of Uganda and will meet with government leaders.