The eldest of the twelve children of Gerontius, the Old Took. Because of his father's famous longevity, Isengrim was already an old Hobbit himself when he inherited the title of Thain, being no less than eighty-eight years old. He did not survive long in his new office, and died just ten years after his father. He was succeeded by his younger brother, who became ThainIsumbras Took IV.
Notes
1
The intended pronunciation of the intial i in Isengrim not entirely clear. See note 1 to the entry for Isengrim Took II for a discussion of the possibilities.
2
Grim in Old English had a much more intense meaning than the modern use of the word, suggesting ferocity or even savagery. So, the name Isengrim, 'iron grim', is a heroic name (actually found in medieval literature) implying iron determination and resolve.