[1] He was born in Raw, County Monaghan, the son of farmers John McCarvill and Susan Moyna.
[2] MacCarvill studied at University College Dublin (UCD) and was a medical doctor, as was his son.
Prior to being fully qualified MacCarvill helped in training of members of Cumann na mBan after the 1916 Easter Rising, and during the Irish War of Independence in first aid in Harcourt Street, along with Kathleen Lynn and Dr Geraghty.
As a result of the selection of MacCarvill, the pro-Treaty side stood an independent candidate Thomas McHugh which forced an election.
[4] He did not contest the September 1927 general election, being succeeded as Fianna Fáil TD by Conn Ward.