Jim Obergefell, the lead plaintiff in the case that legalised same-sex marriage across the United States, is to be honoured.

Being dubbed a civil rights “champion”, Obergefell is to be awarded the Everyday Freedom Hero Award by the National Underground Railroad Freedom Centre in Ohio.

Same-sex marriage was legalised by the Supreme Court in 2015, after Obergefell and his partner John Arthur sought legal recognition of their marriage in Ohio because Arthur was dying.

This led to the case to be heard in the nation’s highest court, where with a majority of five to four, it said bans on same-sex marriage were unconstitutional.

Obergefell has continued to campaign for LGBT equality and Clarence G. Newsome, from the National Underground Railroad Freedom Centre, said he was “a champion of civil rights”.

Earlier this year, Obergefell was invited to President Obama’s final State of the Union address for refusing to give up on having his marriage recognised by his home state.

He has also endorsed Hillary Clinton for President.