Former Vice President Dick Cheney has died at age 84.

Cheney died Monday of complications of pneumonia and cardiac and vascular disease.

The hard-charging conservative became one of the most powerful and polarizing vice presidents and a leading advocate for the invasion of Iraq. Cheney led the armed forces as defense chief during the Persian Gulf War under President George H.W. Bush before returning to public life as vice president under his son, George W. Bush.

In recent years, he became a stout defender of his daughter, Liz Cheney, when she became the leading Republican critic and examiner of Donald Trump’ actions surrounding the Jan. 6, 2021, insurrection at the U.S. Capitol.