My Olin ancestors came to America from Sweden (or Ireland or ...). Are we related to John Olin and Susannah Spencer?

Most Swedish Olins in America arrived here in the 1800's. John and Susannah were here around 1700. Likewise, Olins from other countries have come to America well after John and Susannah. Although these other Olin lines are not descendants of John and Susannah, there is certainly a possibility that they share a common ancestor. Unfortunately, establishing such connections depends on first determining where John originally came from.