Described as "the greatest shipbuilder and shipowner of his day, having at one time shares in 38 vessels" as well as owning considerable
East India Company stock. Later, he had become a bitter opponent of the East India Company and was one of the leading members of the syndicate established in October 1691 to break its monopoly, likely as a result of a dispute with
Sir Josiah Child, 1st Baronet. Johnson succeeded his father in 1683 and was knighted in March 1685. He served as one of the two members of Parliament for
Aldeburgh from 1689 to 1719, his younger brother
William, who died in 1718, being the other member for all but a year of that time. Upon his death in 1719, he was succeeded as by
Walter Plumer after a
by-election. He became an Elder Brother of
Trinity House in 1700 and Master from 1707 to 1709. ==Personal life==