Question: Who is the paternal grandfather of Matilda Of Hesse?
Answer: Louis I

Henry III, Landgrave of Upper Hesse, called "the Rich" (15 October 1440 – 13 January 1483) was the second son of Louis I of Hesse and his wife Anna of Saxony. Upon the death of his father Louis I in 1458, Henry received Upper Hesse and his brother Louis II received Lower Hesse. He succeeded to the title of Landgrave of Hesse-Marburg in 1458