Two great Soldiers who accepted Islam.
1. Bereke Khanthe Mongol who defeated his ruthless cousin Hulaku Khan was a Muslim.
Ibn Kathir said:
السلطان بركه خان بن تولي بن جنكيز خان
وهو ابن عم هولاكو، وقد أسلم بركه خان هذا، وكان يحب العلماء والصالحين ومن أكبر حسناته كسره لهولاكو وتفريق جنوده
Sultan Bereke Khan bin Tawalla bin Genghis Khan was cousin of Hulaku Khan, Bereke Khan accepted Islam and he loved the scholars and the righteous. The best deed he did was to defeat Hulaku and despair his soldiers.
[al Bidaya wal Nihaya vol 13 under the people who died in 665 h]
2. The Crusader who became Muslim and fought against Templars with Saladin, Robert of St Albans.
a. Robert led an Army of Muslims in Jerusalem.
David Hatcher Childress said:
“The English Knight Robert of St Albans left the Templars, became a Moslem and led an army for Saladin against Jerusalem” [Pirates and the Lost Templar Fleet: The Secret Naval War Between the Knights Templar and the Vatican page 94]
b. Robert Married niece of Saladin.
It is mentioned in the book The experience of crusading.
“Another Renegade, Robert of St Albans, an English former Templar, is said by Roger of Howden to have married a niece of Saladin.”
[The experience of crusading, Volume 2 Edited by Peter Edbury, Jonathan P. Phillips, pg.195, Cambridge University Press]
c. Robert was Martyred:
It is mentioned in the book The experience of crusading.
“He devastated the country around Nablus and was killed outside Jerusalem in 1187.” [The experience of crusading, Volume 2 Edited by Peter Edbury, Jonathan P. Phillips, pg.195, Cambridge University Press]