View the most religious surnames in Ireland

Where Does The Last Name O'Brain Come From? ^{nationality or country of origin}

The last name O'Brain is found most frequently in The United States. It may occur as a variant:. For other possible spellings of this last name click here.

How Common Is The Last Name O'Brain? ^{popularity and diffusion}

The surname O'Brain is the 6,360,413^th most commonly occurring last name internationally, held by around 1 in 809,727,324 people. The surname is mostly found in The Americas, where 67 percent of O'Brain are found; 56 percent are found in North America and 56 percent are found in Anglo-North America. O'Brain is also the 3,941,740^th most commonly used first name in the world It is held by 9 people.

This last name is most frequent in The United States, where it is carried by 5 people, or 1 in 72,491,787. In The United States O'Brain is most frequent in: Alabama, where 20 percent reside, Arkansas, where 20 percent reside and Colorado, where 20 percent reside. Other than The United States it occurs in 6 countries. It is also common in Australia, where 22 percent reside and England, where 22 percent reside.

O'Brain Family Population Trend ^{historical fluctuation}

The occurrence of O'Brain has changed through the years. In The United States the number of people who held the O'Brain last name declined 75 percent between 1880 and 2014.

O'Brain Last Name Statistics ^demography

The religious adherence of those carrying the surname is primarily Catholic (100%) in Ireland.