Mohammad Mehdi Shamseddine was born in 1936 in
Najaf,
Iraq.
Allamah al-Shaykh Abdul Kareem Shamseddine was his father and studied at Najaf seminary. When Mohammad was 12 years old, his father returned to Lebanon but Muhammad Mahdi decided to stay and finish his religious studies.
Grand Ayatollah Abul-Qassim Khoei and
Sayed Muhsin al-Hakim were his teachers at Najaf seminary. During his time in the Iraq, he cooperated with
Musa al-Sadr,
Muhammad Baqir al-Sadr, and
Mohammed Baqir al-Hakim. In 1969, he returned to Lebanon and cooperated with Musa al-Sadr for founding the
Supreme Shiite Council of Lebanon. He was first vice-president. Shamseddine was elected as president of the Council in April 1994. Also, he was deputy of Musa al-Sadr organization. == Advocate of coexistence ==