Solomon Moses was the son of Isaac and Reyna Moses and brother of Joshua Moses. His father founded the Bank of New York with Alexander Hamilton and was a merchant active in the China trade. As Solomon came of age, he worked for the family firm and, in 1798, travelled to Madras and Calcutta on business. He also apparently received medical training and practiced medicine, although there are few details about that aspect of his life.

One thing we do know about young Solomon Moses is what a terrible impression he made on the Gratz sisters of Philadelphia—Rachel, Rebecca and Sarah—when in 1804, at the age of thirty, he came to stay with them for a few months. But when he returned two years later, things went quite a bit better, and Rachel fell for the doctor, though she had to convince her sisters he wasn’t as bad as they thought. That summer they were married in Philadelphia. They had nine children. When Rachel died in 1823, the children’s aunt Rebecca would take responsibility for raising them.