Samuel Kamau Wanjiru (10 November 1986 – 15 May 2011) was a Kenyan athlete who specialized in long distance running. He became a professional at a young age and broke the world record in the half marathon when he was 18 years old. In 2007, he broke the 20km road running record and improved the half marathon record by over twenty seconds.

He moved to the full marathon and won the event at the 2008 Beijing Olympics in an Olympic record time of 2:06:32; becoming the first Kenyan to win the Olympic gold in the marathon. The following year, he won both the London Marathon and Chicago Marathon, running the fastest marathons ever recorded in the United Kingdom and United States, respectively. He retained his Chicago title in 2010 in a season fraught with injury.

In 2011, he died after falling off a balcony at his home in Nyahururu following a domestic dispute. Police are still uncertain whether his death was a suicide, homicide, or accidental.

Samuel Kamau was brought up with his brother Simon Njoroge in poverty by his mother Hannah Wanjiru, daughter of Samuel Kamau, and took her given name as a surname, because she was a single mother. He dropped out of school aged about 12, because they could not afford the school fees.

Samuel ( /ˈsæm.juː.əl/;Hebrew: שְׁמוּאֶל, Modern Shmu'el Tiberian Šəmûʼēl; Greek: Σαμουήλ Samouēl; Latin: Samvel; صموئيل, Ṣamu’īl; Strong's: Shemuwel) is a leader of ancient Israel in the Books of Samuel in the Hebrew Bible. He is also known as a prophet and is mentioned in the Qur'an.

His status, as viewed by rabbinical literature, is that he was the last of the Hebrew Judges and the first of the major prophets who began to prophesy inside the Land of Israel. He was thus at the cusp between two eras. According to the text of the Books of Samuel, he also anointed the first two kings of the Kingdom of Israel: Saul and David.

Samuel's mother was Hannah and his father was Elkanah. Hannah, at the beginning of the narrative, is barren and childless, like Abraham's wife Sarah. Hannah prays to God for a child. Eli who is sitting at the foot of the doorpost in the sanctuary at Shiloh, sees her apparently mumbling and thinks Hannah is drunk, but is soon assured of her motivation and sobriety. Eli was, according to the Books of Samuel, the name of a priest of Shiloh, and one of the last Israelite Judges before the rule of kings in ancient Israel. He blesses her after she promises the child to God. Subsequently Hannah becomes pregnant; her child is Samuel. After he is weaned, she leaves him in Eli's care.