Cornelius Brien (Mangane) and Julia McCarthy married in Drimoleague Catholic Parish on 21 February 1860.  The Witnesses were Jeremiah McCarthy and John McCarthy.

We note from the marriage entry that the surname of Cornelius was recorded as Brien (Mangane) and he was one of the Brien clan with the branch name or agnomen Mangane.

Extract from Marriage entry in Church Register:

Cornelius was a son of Pat Mangane and Mary Brien
 

Children: (shown is the surname on the Drimoleague Parish Baptismal Register and the surname on the State Birth Register)

Mary born Gurrane and baptised Brien on 24 Feb 1861 ( birth date is pre State Register era)

Patrick born Gurrane and baptised Mangane on 4 Feb 1863 ( birth date is pre State Register era)

Norry born Clashduv and baptised Mangane on 10 Oct 1865; Brien surname on State Register

Jeremiah born Clashduv and baptised Mangane on 10 Sep 1868; Brien surname on State Register

Elizabeth born Clashduv and baptised Brien on 20 May 1871; Brien surname on State Register

Ellen born Kilmore, Drimoleague and baptised Brien on 9 Aug 1874; Brien surname on State Register

Cornelius born Kilmore and baptised Brien on 20 Jan 1878; Brien surname on State Register

Julia born c. 1880

Census 1901:
http://www.census.nationalarchives.ie/pages/1901/Cork/Bredagh/Clashduff/1153388/

Census 1911:
http://www.census.nationalarchives.ie/pages/1911/Cork/Bredagh/Clashduff/439598/

Deaths:

Julia Brien (nee McCarthy) died at Kilmore, Drimoleague on 27 October 1892.  From her death record she was married, aged 51 years, a dairyman's wife.  The Informan of her death was her husband, Cornelius Brien of Kilmore.

Cornelius Brien died at Clashduv on 28 March 1915.  From his death record he was a widower, aged 79 years, a labourer.  Present at his death and Informant to the Registrar was his son Con Brien of Clashduve.