MSNBC’s Morning Joe co-host, Mika Brzezinski, announced on Friday via Instagram that her father, Zbigniew Brzezinski, has passed away.

My father passed away peacefully tonight. He was known to his friends as Zbig, to his grandchildren as Chief and to his wife as the enduring love of her life. I just knew [sic] his as the most inspiring, loving and devoted father any girl could have. I love you Dad #HailToTheChief

Zbigniew Brzezinski was born in Warsaw, Poland in March of 1928. After attending school and university in Canada, he came to the United States to attend Harvard.

He would go on to advise President Lyndon Johnson and later serve as Pres. Carter’s National Security Advisor.

His work in the field of political science and foreign policy — particularly his work in undermining Soviet influence in satellite countries — for better or worse, made him a notable figure for over five decades.