The "McCann" whom Stephen recalls owing one guinea in Nestor is apparently the "MacCann" with whom Stephen spars in part 5 of A Portrait of the Artist as a Young Man, who in turn is the McCann called "Phil" in Stephen Hero. The character was based on a real-life university friend named Francis Skeffington (after his 1903 marriage to Hanna Sheehy he took the surname Sheehy Skeffington) who was four years older than Joyce but only two classes ahead of him at University College, Dublin. Despite his passionate pacifism, Sheehy Skeffington was arrested by British troops during the Easter Rising and summarily executed.

John Hunt 2022

Francis Sheehy Skeffington in a photograph of unknown date.

Skeffington and Sheehy near the time of their marriage.

Wwallacee's 2020 photograph of public art commemorating "Skeffy," as he was commonly known, in the suburb of Rathmines where he lived and was murdered. Source: Wikimedia Commons.