On January 30, 1912, Scapinelli was appointed Titular Archbishop of Laodicea ad Libanum in association with his diplomatic post to Austria-Hungary.

He received his episcopal consecration on the following February 25 from Cardinal Rafael Merry del Val, with Archbishop Vittorio Ranuzzi de' Bianchi and Bishop Agostino Zampini, OSA serving as co-consecrators, in the Matilda chapel of the Apostolic Palace.

Scapinelli remained in Vienna until the end of 1916, and was awarded with the Grand Cross of the Austrian Order of Sankt Stefan that same year.

The Cardinal later returned to the Roman Curia, serving as Prefect of the Sacred Congregation of the Affairs of Religious from December 19, 1918 until his resignation on March 6, 1920.

Scapinelli was appointed Apostolic Datary on July 22, 1930, and remained in that position until his death three years later, at the age of 75 in Forte dei Marmi.