All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger.
The well-versed scholar Abu Al-ʻAbbaas Al-Hilaali Al-Filaali cited a short biography of Muhammad ‘Abdur-Rahmaan Al-Baghdaadi in his book Noor Al-Basar fi Sharh Khutbat Al-Mukhtasar; however, he did not mention anything about a treatise that he wrote in defense of Ibn Taymiyyah. It is not unlikely given that they were contemporaries.
Al-Hilaali wrote, “Ibn ʻAskar, who passed away in the same year as Shaykh Khaleel, was the well-versed Imaam in intellectual and transmitted sciences (Maʻqool and Manqool), Muhammad ibn ʻAbdur-Rahmaan Al-Baghdaadi. He penned an explanation of Mukhtasar Ibn Al-Haajib Al-Asli (in the principles of Fiqh) and Al-Far‘i (in the Maaliki Fiqh) and a commentary on Al-Irshaad by his father Imaam ʻAbdur-Rahmaan ibn Muhammad ibn ʻAskar Al-Baghdaadi.”
Muhammad Makhloof wrote a short biography on him in his book Shajarat An-Noor Az-Zakiyyah fi Tabaqaat Al-Maalikiyyah, but he did not mention this treatise. He wrote, “The polymath, well-versed, and ingenious scholar, the one who raised the banner of the Maaliki school in Iraq; he was a devout worshipper and one of the refined ascetic scholars. He studied at the hands of his father and other scholars. He authored many books, among them a commentary on Al-Irshaad written by his father, Sharh Mukhtasar Ibn Al-Haajib Al-Asli and Al-Farʻi; he also wrote a lengthy Tafseer and a commentary on ʻIlm Al-Khilaaf (science of legal differences among jurists) and other books in different areas of knowledge. He was born in 701 AH and passed away in 767 AH.”
Allaah Knows best.