Pope Gregory XI reaches Rome, after deciding to move the Papacy back to Rome from Avignon.

Pope Gregory XI was head of the Catholic Church from 30 December 1370 to his death, in March 1378. He was the seventh and last Avignon pope and the most recent French pope. In 1377, Gregory XI returned the papal court to Rome, ending nearly 70 years of papal residency in Avignon, in modern-day France. His death was swiftly followed by the Western Schism involving two Avignon-based antipopes.

Avignon is the prefecture of the Vaucluse department in the Provence-Alpes-Côte d'Azur region of southeastern France. Located on the left bank of the river Rhône, the commune had a population of 93,671 as of the census results of 2017, with about 16,000 living in the ancient town centre enclosed by its medieval walls. It is France's 35th-largest metropolitan area according to INSEE with 337,039 inhabitants (2020), and France's 13th-largest urban unit with 459,533 inhabitants (2020). Its urban area was the fastest-growing in France from 1999 until 2010 with an increase of 76% of its population and an area increase of 136%. The Communauté d'agglomération du Grand Avignon, a cooperation structure of 16 communes, had 197,102 inhabitants in 2022.

January 17 is the 17th day of the year in the Gregorian calendar; 348 days remain until the end of the year.