Barney Frank, a former American lawmaker, known for being the first openly gay congressman and champion for gay rights in the United States, has died. 

According to reports, Mr Frank died on Tuesday night after entering into hospice care at his home in Maine last month. He served as a Democrat member of the U.S. House of Representatives from Massachusetts from 1981 to 2013. 

“He notified everybody that he was in hospice, so it was just a matter of time. He was certainly at peace with himself,” Jim Segel, Mr Frank’s former campaign manager, told Axios.

“He certainly left a mark, and he was a leader on civil rights, on gay rights, on leading other marginalized communities, and then he helped the country get through the 2008 financial crisis, which was the most significant recession, depression, almost since 1930,” Mr Segel added.

He was 86.

During his time at the Capitol Hill, Mr Frank was famous as a pioneer of LGBTQ rights, sponsoring a bill, which would have banned workplace discrimination against workers in the community but was unsuccessful. 

Mr Frank’s most significant legislative achievement in office was the Dodd–Frank Act, which he co-sponsored with former Democratic Senator Chris Dodd. 

The legislation overhauled U.S. banking regulations and introduced stricter financial restrictions in the aftermath of the 2008 financial crisis and the Great Recession.

“He was, above all else, a wonderful brother. I was lucky to be his sister,” Mr Frank’s sister Doris Breay told NBC.