Sibawayhi's book al-Kitab was the first formal and analytical Arabic grammar. It is a groundbreaking work. Some background
Hard to imagine today, but the grandmasters of Arabic grammar were superstars during their lifetime. Here is a list of the TOP 5 Arabic grammarians of all time.
Episode #16 of my series "9273 roots": 20 questions for the man who works for one of the best translation companies for Arabic: Brian Powell