Casimir I the Restorer
Casimir I the Restorer (b. Kraków, 25 July 1016 – d. Poznań, 28 November 1058), was Duke of Poland of the Piast dynasty and the "de jure" monarch of the entire country from 1034 until his death.
He was the only son of Mieszko II Lambert by his wife Richeza, daughter of Count Palatine Ezzo of Lotharingia (of the Ezzonids) and granddaughter of Emperor Otto II.
Casimir is known as "the Restorer" because he managed to reunite all parts of the Polish Kingdom after a period of turmoil.
He reinstated Masovia, Silesia and Pomerania into his realm.
However, he failed to crown himself King of Poland, mainly because of internal and external threats to his rule.
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.
Władysław I Herman
Władysław
I Herman (1044 – 4 June 1102) was a Duke of Poland from 1079 until his death.
He was the second son of
Casimir I the Restorer by his wife Maria Dobroniega, daughter of Vladimir
the Great, Grand Duke of Kiev.
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
Fujiwara no Nagara
, also known as Fujiwara no Nagayoshi, was a Japanese statesman, courtier and politician of the early Heian period.
He was the grandfather of Emperor Yōzei.
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.
Guillaume Wittouck
Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.
He was the Grandfather of industrialist Paul Wittouck.
Prithvipati Shah
Prithvipati Shah( ?–1716) was the king of the Gorkha Kingdom in the Indian subcontinent, present- day Nepal.
He was the grandfather of Nara Bhupal Shah.
Eckhard (bishop of Poznań)
Eckhard, Bishop of Poznań was an 11th- 12th century Catholic Bishop of German descent known from records in the 16th century of the Abbey of Saints Simon and Judas in Goslar.
Before being appointed Bishop he was provost of the Abbey under Franko.
He served as the Bishop at the end of the reign of Władysław Herman who died 1102 AD.

Question: Who is the paternal grandfather of Władysław I Herman?
Answer: Mieszko II Lambert