Montague Isidore Gluckstein
Major Montague Isidore Gluckstein, OBE, (1886–1958) was chairman of J. Lyons and Co. from 1950 to 1956, when he was succeeded by Isidore Montague Gluckstein.
He was the son of Isidore Gluckstein (1851–1920) and his wife Rose Cohen (1851–1908).
Gluckstein took over as chairman from his relative Harry Salmon, who held the post from 1941 to 1950.
Major Gluckstein was involved in the post-war negotiations for a Jewish state, and was described as "a Pukka Sahib anti-Zionist British Jew".
He married Hannah Joseph (b. c. 1889).
John Mackay (poet)
John Mackay( 1656–1754), known as( The Blind Piper), was a Scottish Gaelic poet and composer, and the grandfather of William Ross.
Fred Le Deux
Frederick" Fred" Le Deux( born 4 December 1934) was an Australian rules footballer who played with Geelong in the Victorian Football League( VFL).
He is the grandfather of Tom Hawkins.
Henry Krause
Henry J." Red" Krause, Jr.( August 28, 1913 – February 20, 1987) was an American football offensive lineman in the National Football League for the Brooklyn Dodgers and the Washington Redskins.
He played college football at St. Louis University.
He is the grandfather of Jennifer Krause
He is the great grandfather of Payton Hoeing
Kaya Alp
Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
John Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
Zhao Shoushan
Zhao Shoushan( 12 November 1894 – 20 June 1965) was a KMT general and later Chinese Communist Party politician.
He is the grandfather of Zhao Leji.
Isidore Gluckstein
Isidore Gluckstein (1851–1920) was a director of Salmon & Gluckstein tobacco merchants, and one of the founders of J. Lyons and Co., a restaurant chain, food manufacturing, and hotel conglomerate created in 1884 that dominated British mass-catering in the first half of the twentieth century.
Isidore Gluckstein was the son of Samuel Gluckstein, the founder of Salmon & Gluckstein.
He married Rose Cohen (1851–1908), and they had children:

Question: Who is Montague Isidore Gluckstein's paternal grandfather?
Answer: Samuel Gluckstein