Captain Walter Granger was the 22nd century commander of the Earth ship SS Mariposa.
In 2123, Granger led a colonization mission to the Ficus sector, with a mixed group of colonists ranging from Irish Neo-Transcendentalists to technology-saavy scientists.
Following the departure of the Neo-Transcendentalists on Bringloid V, the Mariposa crash-landed on a class M planet in a neighboring system, ½ light year from the Bringloid system. Only five individuals survived the crash, including Granger. He and his fellow survivors resorted to cloning in order for their colony to survive. (TNG: "Up The Long Ladder")
The clones of Granger were played by Jon De Vries, so we can assume that Captain Granger also looked like him.