Same sex marriage is finally legal in Northern Ireland

Thousands of people take part in a march through Belfast calling for same-sex marriage to be legalized in June 2015.

London (CNN)Same-sex marriage is now legal in Northern Ireland, bringing the province in line with the rest of the United Kingdom, where it has been legal since 2014.

Stormont, the seat of Northern Ireland's devolved legislative power, did not follow England, Wales and Scotland after the British parliament in Westminster voted by a huge majority to legalize same-sex marriage in 2013.
Following the Westminster vote, Stormont held five votes before a slim majority returned a vote in favor of legalization in 2015.
However, this was immediately contested by the Democratic Unionist Party, which tabled a "petition of concern" -- a mechanism that can be used by lawmakers in Stormont to flag up motions before the assembly that could fall across sectarian lines, and so must have both cross-party and cross-community support.