Rueben is of Hebrew origin, meaning 'behold, a son'. It's a variant spelling of Ruben, one of the twelve tribes of Israel and a son of Jacob according to the Old Testament. The name was popular among early Christians due to its biblical roots. Rueben has been used as a given name since the Middle Ages but gained more popularity in the United States during the late 19th century.
"Ruebin was quite popular in 1917, with six babies sharing this unique name that year."